Answer:
0.0979 N/c
Explanation:
Electric field, E is given as a product of resistivity and current density
E=jP where P is resistivity and j is current density
But the current density is given as
where I is current and A is area and 
Substituting this into the first equation then 
Given diameter of 0.259 cm= 0.00259 m and the radius will be half of it which is 0.001295 m

The force ffrom the ground that holds the rock up and prevents her from falling through the gound, unless the ground breaks.
Answer:
7 s
Explanation:
u = Initial velocity of rock = 12.2 m/s
= Angle of throw = 
x = Displacement in x direction = 25 m
Displacement in x direction is given by

Time taken to reach the ground is 7 s.
Well... question 7. kinetic energy is "energy in which a body processes while being in motion" :)