This is due to earths location in the solar system. Earth is in the habitat zone or the Goldie locks zone, in this zone it's not too hot or not too cold for water to exist. Other planets in different star systems have liquid oceans due to them being in the habitat zone.
Answer: The earth is comprised of silicate materials as well as metals. The amount of gas is less here because of its location near to the sun. Due to its relative high surface temperature, the gases such as hydrogen and helium gets evaporated and disappears.
Whereas the sun is entirely comprised of hydrogen and helium gas, of which hydrogen is the dominant one. It has an extremely high temperature of about 5500°C.
Answer:
F = K Q1 Q2 / R^2 where K = 9 * 10E9 (1 / 4 pi ∈0)
F = 9.00E9 * (4.6E-16)^2 / .01 = 1.90E-19 N
C is correct answer.
Walking along a 6 meter beam without falling helps to develop balance.
Hope it helped.
-Charlie