An object of volume has 20ml has a mass of 2.5kg what will be its density​

Need in all of themmm only answer if you know plsssss

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

The transfer of heat through the movement of a gas or liquid a. convection b. conduction c. radiation