Help me answer this please!

Option iv

Explanation:

The acceleration due to gravity (g) of the earth is constant (i.e 9.81 ms¯²). As long as the stone remains within the earth, the acceleration due to gravity experienced by the stone will be 9.81 ms¯².

The maximum height reached by an object is the height where the object no longer have velocity to move further hence it begins to fall back. At this point (i.e at the maximum height), the velocity of the object is zero.

Summary:

At maximum height:

Acceleration due to gravity of the stone = 9.81 ms¯²

Velocity = 0

Thus, option iv gives the correct answer.

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.