You can complete this by solving:

Which should give you .274418 or 27.44%
L would measure at 54°. Because the angels of a triangle measure up to 180, you can set the equation up like this: 5x + 3x + 2x = 180. These are like values, so you can add them together to simplify a bit, yielding 10x = 180. Divide 180 by 10 to get x by itself, giving you 18. L = 3x, so 3(18) = 54.
The Business bought a total of 2048 pens.
Easiest way to solve this is to add the amount of bags the business bought.
7 + 9 = 16
After you find to total amount of bags bought you multiply the amount of pens in each bag by the total amount of bags the business bought.
16 * 128 = 2048
Mainly came from centuries of oppression towards the lower classes by the Tsarist regime and Nicholas's failures in World War I