An Airplane's Speed with Respect to the Air Is 100

Multiple Choice

An airplane's speed with respect to the air is 100 m/sec.The velocity of the air with respect to the ground is 30.0 m/sec to the northeast.What is the direction of the airplane's velocity with respect to the air if the direction of its velocity with respect to the ground is due east?

A) 3.00 degrees south of east
B) 4.50 degrees south of east
C) 12.2 degrees south of east
D) 17.5 degrees south of east