The National Weather Service uses the following formula to calculate the wind chill:
$$
W=35.74+0.6215 T_{a}-35.75 V^{0.16}+0.4275 T_{a} V^{0.16}
$$
where $W$ is the wind chill temperature in ${ }^{\circ} \mathrm{F}, T_{a}$ is the air temperature in ${ }^{\circ} \mathrm{F},$ and $V$ is the wind speed in miles per hour. Note that $W$ is defined only for air temperatures at or lower than $50^{\circ} \mathrm{F}$ and wind speeds above 3 miles per hour.
(a) Suppose the air temperature is $42^{\circ}$ and the wind speed is 7 miles per hour. Find the wind chill temperature. Round your answer to two decimal places.
(b) Suppose the air temperature is $37^{\circ} \mathrm{F}$ and the wind chill temperature is $30^{\circ} \mathrm{F}$. Find the wind speed. Round your answer to two decimal places.