Aman with 70kg body mass is standing in an elevator. we say that upwards is positive direction. what is the sum of the forces (sigma f) when the elevator is moving upwards with an acceleration 2.5m/s^2?

The astronauts on the space shuttle flights experienced an acceleration of 29 m/s2 (about 3 "g's") during lift-off. what upward force must the astronaut's seat apply to the astronaut in order to cause this acceleration? assume the astronaut's mass is 70 kg, and compute this force when the acceleration is near the earth's surface so their weight equals latex: mg m g .