1. 1:0.5 = 8.5:d
2. d = 0.5·8.5 = 4.25
3. compass . . . . the name of the tool/instrument
4. degrees . . . . the graduations on a typical protractor
5. reference . . . . It helps to be a little familiar with navigation terms
6. bearing
7. 310 . . . . the number in the picture
_____
If you have not had any exposure to navigation terms or methods, orienteering, map orientation, map reading, or any similar activity, it would be difficult to answer these questions appropriately. Hopefully, your text explains this in some detail. It is helpful to get a map and compass and do some navigation yourself in order to see how this works. Boy/Girl Scouts used to do activities of this sort.