Answer: option c.
Step-by-step explanation:
You need to remember the identity:

The inverse of the tangent function is arctangent. You need to use this to calculate the angle "R":
You know that you need to find the measure of "R" and
(which is the opposite side) and
(which is the adjacent side), you can sustitute values into 
Then, you get:

Answer:
40 %
Step-by-step explanation:
2 divided by 30 and you get .4 which is the same as 40%
Hope this helps :)
Well whats theproblem so we can figure it out?