G(a) = a^2+3a f(a)= 3a - 2 Find (gºf)(a)
I don't understand how to do composition of functions​

Astandard deck of cards contains 52 cards. one card is selected from the deck. (a) compute the probability of randomly selecting a seven or king. (b) compute the probability of randomly selecting a seven or king or jack. (c) compute the probability of randomly selecting a queen or spade.

Write an expression that has three terms and simplifies to 4x - 7. identify the coefficient(s) and constant(s) in your expression

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.