I need to know before tomorrow

The magnitude of the force of gravity acting on an object is called its... weight! Your weight is equal to your mass times the local value of acceleration due to gravity, which on the surface of the earth we call "g" and has an approximate value of 9.8 m/s^2. Thus your weight on the earth's surface is calculated from:

W = m*g

Example: if your mass is 100Kg, then your weight on Earth measured in Newtons is:

W = 100 kg * 9.8 m/s^2 = 980 N.