An 11-kilogram cart is pulled with a horizontal force at a constant velocity of 8.0 meters per second, as shown in the diagram. The force of friction between the cart and the floor is 12 newtons. What is the magnitude of the horizontal force?

The cart is in equilibrium since it's moving at a constant velocity. This means the net horizontal force on the cart is 0, so the frictional force and pulling force cancel one another. So the pulling force has magnitude 12 N, same as the frictional force.

d is the answer i came up with

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees.