When the space shuttle coasts in a circular orbit at constant speed about the earth, is it accelerating? if so, in what direction?

Yes. Acceleration means any change in speed or direction of motion. When an object coasts in a circular orbit at constant speed around the Earth, its direction is constantly changing. The acceleration is "CENTRIPETAL", which points toward the center of the circle.

B) as the temperature increases, the kinetic energy of the particles increases.|-/