$2.$ Short Answer $($work and answers on separate sheet$).$ Each of the following problems are worth $3$ points.

a$)$ Determine in pounds the drag on a bicyclist racing to ME$120$ at $18$ mph into a $12$ mph headwind of $\backslash (59^\{\backslash$circ$\}\backslash$mathrm$\{$F$\}\backslash )$ air $($the bicyclist is in a racing position and the wind is blowing towards them$).$ Also determine the horsepower to overcome this drag. $1$ mile $=5280$ feet.

b$)$ The density of air in Table $1\mathrm{.}8$ is $\backslash (1\mathrm{.}23\backslash$mathrm$\{$~kg$\}/\backslash$mathrm$\{$m$\}^\{3\}\backslash ).$ What's a typical high altitude air density? Calculate air's density at a an elevation where the temperature is $\backslash (-30^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ and the absolute pressure is $41$ kPa

c$)$ Air's drag force on the roof of a moving van is $18\mathrm{.}5$ pounds. The roof's dimensions are $8$ feet by $12$ feet. Determine the direction and magnitude air's shear on the roof.

d$)$ Pipe A contains gasoline while pipe B contains SAE $30$ oil. The gasoline at point $\backslash ($ A $\backslash )$ is at gage pressure $36\mathrm{.}4$ kPa $.$ The two pipes are connected by a manometer. Determine the gage pressure at point $\backslash ($ B $\backslash ).$ Use values from Tables $1\mathrm{.}6$ in your calculations.

e$)$ A boxy car moves at $7\mathrm{.}5$

$\backslash (\backslash$mathrm$\{$mph$\}(11\backslash$mathrm$\{$feet$\}/\backslash$mathrm$\{$sec$\})\backslash )$ through still $\backslash (59^\{\backslash$circ$\}\backslash$mathrm$\{$F$\}\backslash )$ standard air. The top of the car is essentially a flat plate of length $7$ feet and width $6$ feet. Determine the air Reynolds number at the car roof's trailing $($i$.$e$.$ rear$)$ edge

f$)$ For the car in problem $2$ e$,$ determine the boundary layer height in inches at the rear edge of the car's roof.