The two spheres above have the same center. one has a radius of 4 cm, and the other has a radius of 5 cm. approximately how much space is in between the two spheres?

The space between the two spheres will be the volume of the larger sphere minus the volume of the smaller sphere.  Given that the volume of any sphere is:

V=(4πr^3)/3  The space between to sphere of different radius and positioned about the same center is:

S=(4πR^3)/3-(4πr^3)/3  I used S=volume of space, R=larger radius and r=smaller radius...

S=(4π/3)(R^3-r^3), we are told that R=5 and r=4 so

S=(4π/3)(5^3-4^3)

S=(4π/3)(125-64)

S=(4π/3)(61)

S=244π/61

S=4π cm^3

S≈12.57 cm^3  (to nearest hundredth of a ml)

I’m confused as to what you are asking 66 2/3 percentage wise