An Airplane Is Traveling At $150 \mathrm{~m} / \mathrm{s}$ In Level Flight

Multiple Choice

An airplane is traveling at $150 \mathrm{~m} / \mathrm{s}$ in level flight. In order to make a change in direction, the airplane travels in a horizontal curved path. To fly in the curved path, the pilot banks the airplane at an angle such that the lift has a horizontal component that provides the horizontal radial acceleration to move in a horizontal circular path. If the airplane is banked at an angle of 12.0 degrees, then the radius of curvature of the curved path of the airplane is

A) $8.74 \mathrm{~km}$ .
B) $6.90 \mathrm{~km}$
C) $7.33 \mathrm{~km}$ .
D) $10.8 \mathrm{~km}$
E) $8.00 \mathrm{~km}$ .