How to find circumference if circles

An equation representing lyle’s hedge-trimming business is a = 12n - 300 where a is the amount of profit or loss in dollars and n is the number of hedges trimmed. how would the graph of lyle’s business change if the equation a = 10n - 300 represented his business? the graph would be flatter. the graph would be steeper. the graph would start closer to the origin. the graph would start lower on the y-axis.

What is the image of c for a 90° counterclockwise rotation about a? (3, 7) (-1, 3) (7, 3)

Solve the triangle. a = 21°, c = 105°, c = 5