Related Questions

The popular notion that a tree's age can be determined by counting number of internal rings in its trunk is generally true. Howeevr, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often →peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So only if the temperature in the Brazilian ash's environment never exceeds 95 degrees Fahrenheit →elav eing the tree with fewer rings than it would otherwise have. So only if the reliable measure of the tree's age. Which of the following is an assumption on whish the argument above depends?
A The growth of new rings in a trees is not a function of levels of precipitation.
B Only the Brazilaian ash loses rings because of excessive heat.
C One day of temperatures above 95 degrees Fahrenheit will cause the Brazilian ash to lose one ring.
D The internal rings of all tress are of uniform thickness
In most of the vacuum crystalliser, vacuum is generally produced by means of a
A Suction pump
B Compressed air jet
C Steam jet ejector with a barometric condenser
D None of these
Vacuum is applied in __________ zone, in case of a general type continuous rotary drum vacuum filter.
A Filtering
B Washing
C Drying
D All of the above
Vacuum maintained in the vacuum distillation column in oil refinery is in the range of about __________ mm Hg absolute.
A 1 to 5
B 30 to 80
C 250 to 350
D 450 to 500
The vacuum maintained in vacuum distillation unit for reduced crude is about __________ mmHg.
A 1.2
B 12
C 120
D 700
Vacuum maintained in the vacuum distillation tower of the crude distillation plant is about __________ mm Hg (absolute).
A 5-10
B 30-80
C 150-250
D 350-400
Natural rubber is obtained from latex, which is a colloidal dispersion of rubber in water. Which of the following is used as a coagulant in latex?
A Ammonium alum
B Potassium alum
C Both A & B
D Neither A nor B
Styrene-butadiene-rubber (SBR) as compared to natural rubber has
A Poorer tensile strength
B Poorer resistance to oxidation
C Greater amount of heat build-up under heavy loading
D All of the above
Styrene butadiene rubber (SBR) as compared to natural rubber has
A Poor tensile strength
B Poorer resistance
C Greater amount of heat build up heavy loading
D All of the above
The ratio of the actual vacuum to the ideal vacuum in a condenser is called
A Condenser efficiency
B Vacuum efficiency
C Nozzle efficiency
D Boiler efficiency

Next steps