Calculate the speed in m/s at which the moon revolves around the earth. note: the orbit is nearly circular.

1020 m/s

Explanation:

The moon is in the earth's orbit, meaning it is in free fall.  Its centripetal acceleration is equal to the acceleration due to gravity.

v² / r = GM / r²

v² = GM / r

v = √(GM / r)

G is the universal gravitational constant, M is the mass of the earth, and r is the distance from the earth's center to the moon's center.

G = 6.67×10⁻¹¹ m³/kg/s²

M = 5.97×10²⁴ kg

r = 3.84×10⁸ m

v = √( (6.67×10⁻¹¹) (5.97×10²⁴) / (3.84×10⁸) )

v = 1020 m/s

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle

it was given as a lesson and guide for prayer.