What is the difference between a full Moon and a a new Moon ?

Moon is

After how many days a full Moon changes into a new Moon ?

The mass of the earth is 81 times the mass of the Moon and the distance between the earth and the Moon is 60 time the, radius of the earth. If R is the radius of the earth, then the distance between the Moon and the point on the in joining the Moon and the earth where the gravitational force becomes zero is

What is the radius of the moon?

What happens to the moon after full moon day?

State whether the following statements are true or false: Occuring of the full moon and new moon is a periodic change.