How big would the aperture of a telescope

Question

On the earth, determine how big would the aperture of a telescope have to be in order to view a 6 ft (1.83m) astronaut walking on the moon? (The moon is around 3.8 x 10⁸ m from the earth; employ λ = 550nm).

i) 4.7 x 10^-6m

ii) 114m

iii) 1.39 x 10²m

iv) 1.4 x 10¹¹m

v) 1.4 x 10²⁰m