TeX source:

WCI30 = \left\{ \begin{array}{lll}30^o & \mbox { if  0  ≤ v  ≤ 4 mph}\\62.19  - 18.70 \sqrt v + 1.25v & \mbox { if  4 ≤ v ≤ 45 mph}\\-7^o & \mbox { if 45 ≤ v mph} \end{array} \right\}