Solve the Problem $\frac { x ^ { 2 } } { 21 } - \frac { y ^ { 2 } } { 20 } = 1$

Multiple Choice

Solve the problem.
-A comet follows the hyperbolic path described by $\frac { x ^ { 2 } } { 21 } - \frac { y ^ { 2 } } { 20 } = 1$ , where $x$ and $y$ are in millions. If the sun is the fc of the path, how close to the sun is the vertex of the path?

A) $4.6$ million
B) 41 million
C) $6.4$ million
D) $1.8$ million