What is the slope of the line that passes through the points (3, 1) and (8, 3)?

a) -5/2
b) 2/5
c) -2/5
d) 5/2

Acar dealership pays you 5% commission on your first $10,000 on car sales and 8% commission on the sale amount over $10,000 if you sold a $12,000 car how much is your commission

Can some one me, i’ve been asking for so long

How do i do this? i don’t understand