How does night be warm when the day is cool?

How many neutrons does element x if it’s atomic number is 28 and its mass number is 87

What is a subatomic particle with a negative charge and very little mass?

A14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.