An airplane flies at \(150 \mathrm{~km} / \mathrm{hr}\).

(a) The airplane is towing a banner that is \(b=0.8 \mathrm{~m}\) tall and \(\ell=25 \mathrm{~m}\) long. If the drag coefficient based on area \(b \ell\) is \(C_{D}=0.06\), estimate the power required to tow the banner.

(b) For comparison, determine the power required if the airplane was instead able to tow a rigid flat plate of the same size.

(c) Explain why one had a larger power requirement (and larger drag) than the other.

(d) Finally, determine the power required if the airplane was towing a smooth spherical balloon with a diameter of \(2 \mathrm{~m}\).