With the force directly proportional to the product of the masses and inversely proportional to the square of the distance between them...
(d) option is right answer
<span>Without convection, the equator would stay smoldering hot, the poles would stay well in the deep freeze, and places in between would be in between. The currents move the warm air and warm water from the tropics up to the poles and move cold air and water from the poles down to the tropics. Until now, the coasts have enjoyed milder weather because of the convection currents. -Hope this helps!</span>
45N
The normal is perpendicular to the forces that go up or down the slope. The downward force is just the weight .