Does anyone know the answer?

What is the exact volume of the cylinder (radius 13 in., height 30 in.)

Write the system of equations represented by the matrix. 0 1 2 4 -2 3 6 9 1 0 1 3

Apatient is given 50 mg dose of medicine the medicines effectiveness decreases every hour at a constant rate of 40% what is the exponential decay function that models this scenario how much medicine will be left in the patients system after 2 hours