Related Questions

When certain geometric requirements are met, X-rays scattered from a crystalline solid can constructively interfere with each other and produce a diffracted beam.
124λ তরঙ্গদৈর্ঘ্যের এক রঙা এক্সরে একটি কার্বণ ব্লক দ্বারা বিক্ষিপ্ত হয়। 180° তে এক্সবের বিক্ষিপ্ত বিকিরণের তরঙ্গদৈর্ঘ্যের মান নির্ণয় কর।(A monochromatic X-rays of wavelength 0.124λ is scattered by a carbon block. Find the wavelength of X-rays scattered through 180°) 
A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series. Gama rays, X­rays, Ultraviolet rays, ? , Infrared rays
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Ants have been living on the earth for more than 100 million years and can be found almost anywhere on the planet. It is estimated that there are about 20000 different species of ants. For this reason ants have been called Earth's most successful species. If you watch ants for any length of time you will see that they really do communicate with each other and very effectively too. Ants communicate by touching each other with their antennae. Ants also use chemicals called pheromones to leave scent trails for other ants to follow. Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnels up to 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don't make a home at all but travel in a large groups searching for food. Ants are social insects which means they live in large colonies or groups. Some colonies consist of millions of ants. There are three types of ants in each species, the queen, the sterile female workers and males. The male ants only serve one purpose, to mate with future queen ants and do not live very long. The queen grows to adulthood, mates, and then spends rest of her life laying eggs. A colony may have only one queen, or there may be many queens depending on the species. Ants go through four stages of development: egg, larva, pupa and adult.
Why are ants called the 'Earth's' most successful species?
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Ants have been living on the earth for more than 100 million years and can be found almost anywhere on the planet. It is estimated that there are about 20000 different species of ants. For this reason ants have been called Earth's most successful species. If you watch ants for any length of time you will see that they really do communicate with each other and very effectively too. Ants communicate by touching each other with their antennae. Ants also use chemicals called pheromones to leave scent trails for other ants to follow. Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnels up to 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don't make a home at all but travel in a large groups searching for food. Ants are social insects which means they live in large colonies or groups. Some colonies consist of millions of ants. There are three types of ants in each species, the queen, the sterile female workers and males. The male ants only serve one purpose, to mate with future queen ants and do not live very long. The queen grows to adulthood, mates, and then spends rest of her life laying eggs. A colony may have only one queen, or there may be many queens depending on the species. Ants go through four stages of development: egg, larva, pupa and adult. Antennae are used by ants to
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Ants have been living on the earth for more than 100 million years and can be found almost anywhere on the planet. It is estimated that there are about 20000 different species of ants. For this reason ants have been called Earth's most successful species. If you watch ants for any length of time you will see that they really do communicate with each other and very effectively too. Ants communicate by touching each other with their antennae. Ants also use chemicals called pheromones to leave scent trails for other ants to follow. Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnels up to 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don't make a home at all but travel in a large groups searching for food. Ants are social insects which means they live in large colonies or groups. Some colonies consist of millions of ants. There are three types of ants in each species, the queen, the sterile female workers and males. The male ants only serve one purpose, to mate with future queen ants and do not live very long. The queen grows to adulthood, mates, and then spends rest of her life laying eggs. A colony may have only one queen, or there may be many queens depending on the species. Ants go through four stages of development: egg, larva, pupa and adult. What does the Western Harvester do in winter ?
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Ants have been living on the earth for more than 100 million years and can be found almost anywhere on the planet. It is estimated that there are about 20000 different species of ants. For this reason ants have been called Earth's most successful species. If you watch ants for any length of time you will see that they really do communicate with each other and very effectively too. Ants communicate by touching each other with their antennae. Ants also use chemicals called pheromones to leave scent trails for other ants to follow. Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnels up to 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don't make a home at all but travel in a large groups searching for food. Ants are social insects which means they live in large colonies or groups. Some colonies consist of millions of ants. There are three types of ants in each species, the queen, the sterile female workers and males. The male ants only serve one purpose, to mate with future queen ants and do not live very long. The queen grows to adulthood, mates, and then spends rest of her life laying eggs. A colony may have only one queen, or there may be many queens depending on the species. Ants go through four stages of development: egg, larva, pupa and adult. What kind of homes do the army of ants build ?
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it.
Ants have been living on the earth for more than 100 million years and can be found almost anywhere on the planet. It is estimated that there are about 20000 different species of ants. For this reason ants have been called Earth's most successful species. If you watch ants for any length of time you will see that they really do communicate with each other and very effectively too. Ants communicate by touching each other with their antennae. Ants also use chemicals called pheromones to leave scent trails for other ants to follow. Ants build many different types of homes. Many ants build simple little mounds out of dirt or sand. Other ants use small sticks mixed with dirt and sand to make a stronger mound that offers protection from rain. Western Harvester ants make a small mound on top, but then tunnels up to 15 feet straight down to hibernate during winter. Ant mounds consist of many chambers connected by tunnels. Different chambers are used for nurseries, food storage, and resting places for the worker ants. Some ants live in wood like termites. Army ants don't make a home at all but travel in a large groups searching for food. Ants are social insects which means they live in large colonies or groups. Some colonies consist of millions of ants. There are three types of ants in each species, the queen, the sterile female workers and males. The male ants only serve one purpose, to mate with future queen ants and do not live very long. The queen grows to adulthood, mates, and then spends rest of her life laying eggs. A colony may have only one queen, or there may be many queens depending on the species. Ants go through four stages of development: egg, larva, pupa and adult. What is the purpose of male ants ?
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Most economists in the United States seem captivated by the spell of the free market. Consequently, nothing seems good or normal that does notaccord with the requirements of the free market. A price that is determined by the seller or, for that matter (for that matter: so far as that isconcerned), established by anyone other than the aggregate of consumers seems pernicious. Accordingly, it requires a major act of will to thinkof price-fixing (the determination of prices by the seller) as both "normal" and having a valuable economic function. In fact, price-fixing is normalin all industrialized societies because the industrial system itself provides, as an effortless consequence of its own development, the price-fixingthat it requires. Modern industrial planning requires and rewards great size. Hence, a comparatively small number of large firms will be competingfor the same group of consumers. That each large firm will act with consideration of its own needs and thus avoid selling its products for morethan its competitors charge is commonly recognized by advocates of free-market economic theories. But each large firm will also act with fullconsideration of the needs that it has in common with the other large firms competing for the same customers.
What does not seem as not good or normal in the context of this essay?
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Most economists in the United States seem captivated by the spell of the free market. Consequently, nothing seems good or normal that does notaccord with the requirements of the free market. A price that is determined by the seller or, for that matter (for that matter: so far as that isconcerned), established by anyone other than the aggregate of consumers seems pernicious. Accordingly, it requires a major act of will to thinkof price-fixing (the determination of prices by the seller) as both "normal" and having a valuable economic function. In fact, price-fixing is normalin all industrialized societies because the industrial system itself provides, as an effortless consequence of its own development, the price-fixingthat it requires. Modern industrial planning requires and rewards great size. Hence, a comparatively small number of large firms will be competingfor the same group of consumers. That each large firm will act with consideration of its own needs and thus avoid selling its products for morethan its competitors charge is commonly recognized by advocates of free-market economic theories. But each large firm will also act with fullconsideration of the needs that it has in common with the other large firms competing for the same customers. Who, according to the economists, are the right group of people to set the price of a commodity?