Ahelicopter lifts a 66 kg astronaut 15 m vertically from the ocean by means of a cable. the acceleration of the astronaut is g/11. how much work is done on the astronaut by (a) the force from the helicopter and (b) the gravitational force on her? just before she reaches the helicopter, what are her (c) kinetic energy and (d) speed?

Explain vector addition, triangle method and parallelogram method

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?