Can someone answer. there's one problem. there's a picture. you!

Maria donates a fixed amount, a, to a charity each month. if she donates $300 in 12 months, what is the equation for a? a. a + 300 = 12 b. a × 300 = 12 c. a × 12 = 300 d. a + 12 = 300 e. a + 32 = 100

Find the quotient. 50a2 – 98b2 -5a +7b

How do you find the circumfrance of a circle?