Please i really need help with this

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Two angles are complementary. the large angle is 36 more than the smaller angle. what is the measure of the large angle?

Question 5 of 10 2 points if a population is a sample of the population could be a. registered voters; all citizens o o b. baptists; all religious people o c. people who purchased shoes; all customers o d. the entire school faculty; math teachers