Answer: if the mass is doubled, the force of gravity is doubled, meaning it decreases. If the distance is doubled, the force of gravity is 1/4 as strong as before
Explanation:
Answer:

Explanation:
We have given initial length of the steel guitar l = 1 m
Cross sectional area 
Young's modulus 
Force F = 1500 N
So stress 
We know that young's modulus 
So 

Now strain 


Answer: Strength of magnet and distance from magnetic material
Explanation:
The potential energy of a magnet is determined by the strength of the magnet and the distance between a magnet and another magnet or a magnetic material. Magnetic materials are materials that would be attracted when brought close to a magnet, example of magnetic materials are most metals.
politics. Famous possible eg is of Werner Heisenberg in WW2. He delayed German attempt to build a nuclear bomb. US did build one ... hiroshima and nagasaki.
debbie may have got skilfully lucky by trial and error