Answer:
C.
Step-by-step explanation:
use the pythogorean theorem a^2 + b^2 = c^2
The formula of an area of a triangle:

We have:

substitute:

The formula of an area of a circle:

We have 
Substitute:

The area of the shaded region

All of the given numbers are both real and rational, and so all of their respective squares are also real and rational.
Answer:
C
Step-by-step explanation:
N = st
Number of toothpicks = (number of students) x (toothpicks)