(4) (5 pts) Set up, but do NOT evaluate, the integral needed to determine the mass M of a plate with a radius of 16 cm and a radial density given by p(x) = 1+2sin(x), in Kg/cm, with x in cm. Do NOT Evaluate. M = = Units: (5) (8 pts) A spring that obeys Hooke's law has a spring constant k = 50 N/m and a natural length 10 meters (m). Compute the force F(x) (and units) then Compute the work (and units) required to stretch the spring starting from a stretched total length of 12 m to a stretched total length of 15 m. W = F = Units: Units: