I have backed up the pictures from my phone to a USB drive, but my Windows 7 PC cannot read APK files. What do I do?

Use your file explorer app on windows to find where you stored your photos. It can be in a photos folder, a folder marked "DCIM" albums, download, etc. Photos themselves are never stored"inside" an apk, on your Android phone but can often be stored in obscure places in androids file system. So whenever you take, store, or move a picture, you need to tell your phone where you want it stored...Most apk's will have an option in their settings memo that allow you to set a "directory" or folder where you want your photos stored. If confused get a tech savvy friend to show you how.