Two balls are kicked with the same initial speeds. ball a was kicked at the angle 20° above horizontal and ball b was kicked at the angle 75° above horizontal. what ball will have bigger speed at the highest point of their trajectory? (section 4.3) ball a ball b impossible to answer without knowing their actual initial speeds. they will have the same speeds

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.