When the Earth, Moon, and Sun form a right triangle, with the Moon located at the right

Question:

When the Earth, Moon, and Sun form a right triangle, with the Moon located at the right angle, as shown in FIGURE 12-34, the Moon is in its third-quarter phase. (The Earth is viewed here from above its North Pole.) Find the magnitude and direction of the net force exerted on the Moon. Give the direction relative to the line connecting the Moon and the Sun.