A Baseball Diamond Is a Square with Side 90 Ft $22 \frac { \mathrm { ft } } { \mathrm { sec } }$

A baseball diamond is a square with side 90 ft. A batter at the home base hits the ball and runs toward first base with a speed of $22 \frac { \mathrm { ft } } { \mathrm { sec } }$ . At what rate is his distance from third base increasing when he is halfway to first base ? Round your answer to the one decimal place.

A) $5.5 \frac { \mathrm { ft } } { \mathrm { sec } }$
B) $11.0 \frac { \mathrm { ft } } { \mathrm { sec } }$
C) $9.8 \frac { \mathrm { ft } } { \mathrm { sec } }$
D) $15.6 \frac { \mathrm { ft } } { \mathrm { sec } }$
E) $49.2 \frac { \mathrm { ft } } { \mathrm { sec } }$