Please help ?

Prove that the diagonals of a rectangle bisect each other.
Name the coordinates for point C.

A: (b, a)

B: (2a, 2b)

C: (a, b)

D: (2b, 2a)

Aclass consists of 55% boys and 45% girls. it is observed that 25% of the class are boys and scored an a on the test, and 35% of the class are girls and scored an a on the test. if a student is chosen at random and is found to be a girl, the probability that the student scored an ais

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

If you can solve all of these i will give ! - 4% of 190 - 4% of 162.5 - 4% of 140 - a 4% increase from 155.1 - a 4% increase from 159.8