physics?

<p>Can somebody help me answer these questions with work shown please? thanks.</p>

<ol>
<li><p>calculate the force of gravitational attraction between two spheres of mass 10.1 kg and 45.4 kg that are 38.5 m apart.</p></li>
<li><p>A 69.8 kg student sits at a desk 1.75 m away from a 78.9 kg student. What is the magnitude of the gravitational force between the two students? (G=6.673 x 10^-11 N.m^2/kg^2)</p></li>
<li><p>By what factor would your weight be multiplied if Earth were 1/2 as massive and Earth's diameter remained unchanged?</p></li>
<li><p>Imagine you are standing atop a ladder so tall that you are 2 Earth radii from Earth's center. What is your weight at the top of the ladder, relative to your weight on the ground?</p></li>
</ol>

<p>Can somebody please help me with these problems?</p>

<p>Just use:</p>

<p>F= (GM1M2)/(r^2)</p>