Answer:
(I). The Schwarzschild radius is 
(II). The Schwarzschild radius is 17.7 km.
(III). The Schwarzschild radius is 
(IV). The Schwarzschild radius is 
Explanation:
Given that,
Mass of black hole 
(I). We need to calculate the Schwarzschild radius
Using formula of radius

Where, G = gravitational constant
M = mass
c = speed of light
Put the value into the formula


(II). Mass of block hole 
We need to calculate the Schwarzschild radius
Using formula of radius

Put the value into the formula


(III). Mass of block hole m= mass of moon
We need to calculate the Schwarzschild radius
Using formula of radius

Put the value into the formula


(IV). Mass = 50 kg
We need to calculate the Schwarzschild radius
Using formula of radius

Put the value into the formula


Hence, (I). The Schwarzschild radius is 
(II). The Schwarzschild radius is 17.7 km.
(III). The Schwarzschild radius is 
(IV). The Schwarzschild radius is 