Can anyone help me to get the answers for these problems

On a piece of paper graph f(x)=5•(0.4)^x

What are the measures of angles a, b, and c? show your work and explain your answers. 25 points

Asunflower was 20 1/2 inches tall. over the next 6 months, it grew to a height of 37 inches tall. what was the average yearly growth rate of the height of the sunflower? ? plz write a proportion to solve i will give you 100 points