#### Answer

$h = 716~mi$

#### Work Step by Step

$h = R~(\frac{1}{cos~\frac{180~T}{P}}-1)$
We can find $h$ when $T = 25~min$ and $P = 140~min$:
$h = R~(\frac{1}{cos~\frac{180~T}{P}}-1)$
$h = (3955~mi)~(\frac{1}{cos~\frac{(180)(25~min)}{140~min}}-1)$
$h = 716~mi$