At what height above the earth would the weight of a man become half its surface value

Orque can be calculated by multiplying the force (n) applied at 90? to the lever arm at a distance (m) from the pivot point (point of rotation), the compound si unit for the torque is n? m. if the force (at 90? to the lever arm) applied is 15 n and it is applied at 2.0 m from the pivot point (point of rotation), what is the torque on the lever?

True or false: the revolution of the earth creates day and night as it rotates around the sun

If a tank filled with water contains a block and the height of the water above point a within the block is 0.8 meter, what is the pressure at point a?