Ground-based radio telescopes can collect data from distant objects in space A.
during the night only and in any weather conditions.
B.
during the day or night and in any weather conditions.
C.
during the day or night and in clear weather only.
D.
during the night only and in clear weather only.

Iassume the answer is 75 feet. inwards to outwards rather than outwards to inwards. probably be 75.hachures are stokes drawn in direction of the steepest slope. a series of short parallel lines drawn on a map to indicate topographic relief. it is actually called hachures on contour lines. the small marks in the center of the feature are called hachures.observe the picture attached

Iwould think it would be efficiency.