Answer
$4060$ miles and $100$ miles
Work Step by Step
We have $ r=\dfrac{4090.76}{1-0.0076 \cos \theta}$
or, $ r=\dfrac{4090.76}{1-0.0076 \cos (\pi)}$
(we use $\theta=\pi$ for the minimum distance from the center of the Earth.)
or, $ r =\dfrac{4090.76}{1+0.0076}\approx 4060$ miles
We subtract the average radius of the Earth to get the distance from the surface of the Earth:
$4060-3960=100$ miles
