Please find the slope, thank you

Ebuka's monthly rent is $750. if ebuka pays the rent late, his landlord charges 4% interest per week that the payment is late. write a function that gives the total cost r(t), in dollars, of ebuka's rent if he pays it t weeks late.

Lana's family entered a 5-kilometer race lana's average step length is about 0.5 meter how many steps will she need to take the finish

What is the slope of any line parallel to the line 8x+9y=3 in the standard (x, y) coordinate plane?