Aflat disk, a solid sphere, and a hollow sphere each have the same mass m and radius r. the three objects are arranged so that an axis of rotation passes through the center of each object. the rotation axis is perpendicular to the plane of the flat disk. which of the three objects has the largest moment of inertia?

On a mild saturday morning while people are working inside, the furnace keeps the temperature inside the building at 23degreesc. at noon the furnace is turned off, and the people go home. the temperature outside is a constant 16degreesc for the rest of the afternoon. if the time constant for the building is 3 hr, when will the temperature inside the building reach 18degreesc? if some windows are left open and the time constant drops to 2 hr, when will the temperature inside reach 18degreesc?