First pic ; they are complementary angles , so C !!
second pic ; both angles are supplementary angles !! as sum is 180° !!
Answer:
-99
Step-by-step explanation:

Answer:
The answer for standard deviation would be:
4.382
50/80 = 0.625
100 - 0.625 = 0.375
0.375 = 37.5% (move the decimal point to the right 2 spaces)
37.5% decrease is your answer
hope this helps