There are two bodies of i) a metal and ii) a material plastic (look for its properties) that you want to submit to a process metallurgical water quenching whose heat transfer coefficient is 10W/m2C. The temperature of the bodies when they come out of the oven is 700 C and the quenching water temperature is 20 C. Find the time required for both bodies to reach a temperature of 350 C if the bodies are a) a sphere with a diameter of 10 cm, b) a cylinder with a diameter and length of 10 cm and c) a cube of 10 cm sideways. Also find the Biot number for each case.