The engine displacement of an automobile is the volume through which the piston moves from high to low position. If an engine has "n" cylinders, the displacement is D = π(bore÷2)² • stroke • n, where the bore is the diameter of the cylinder and stroke is the length of the piston's travel. 1) If bore = and stroke = h, simplify the expression, D, in terms of k and h for 8 cylinders.

2) If the bore is 4 inches, the stroke is 3.4 inches, and the engine has four cylinders, what is the displacement? Round your answer to the nearest tenth of a cubic inch.

please help. I really want to understand.