Movement of air from land to sea at night, created when cooler, denser air from the land forces up warmer air over the sea.
a. land breeze
b. sea breeze
c. coriolis effect

The correct answer is land breeze.

Explanation:

Land breeze : A wind system moving from land to ocean that is moment of wind from land to sea or ocean. As land cools down quickly than sea water due to which hot air present above the sea water rises above and cold air from land moves towards the sea creating breeze.

Where as:

Sea breeze is a wind system in which wind from sea blows towards the land.

Coriolis effect is change in direction of an moving freelyu moving object due to rotation of the Earth.

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg

3. dark matter

empty space could also be a simple vacuum