The measure of an angle is 78°. what is the measure of a complementary angle?

First you need to know the definition of a complementary angle. That means that two angles add up to 90 degrees, or a right angle.

To find an angle complementary to a 78 degree angle, you need to subtract 78 from 90. 

90 - 78 = 12

What is the last question i don’t see it?

Claude debussy's music was associated with answer choice 3, impressionist