Aboat with an anchor on board floats in a swimming pool that is somewhat wider than the boat. does the pool water level move up, move down, or remain the same if the anchor is (a) dropped into the water or (b) thrown onto the surrounding ground

dropped

Explanation:

It is given that the first anchor is on the boat and then it was thrown in the swimming pool then the level of water will decrease as according to Archimedes principle when a body floats in water it displaces water equals its weight.

Initially, total anchor weight is supported by buoyancy but as soon as it is thrown into swimming pool is sinks and level of water come down .

The buoyancy force is large when anchor is in boat i.e. it displaces more water than its weight.      

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.