Consider a vector in 3$3$ dimensions that describes the velocity of an airplane after taking off. It has components vx=313.9,$=313\mathrm{.}9,$ vy=492.0,$=492\mathrm{.}0,$ and vz=400$=400$ km/$/$h,$,$ where "$"$x"$"$ is to the east, "$"$y"$"$ to the north, and "$"$z"$"$ is height above Earth's surface .$.$ The climb is brief because at an altitude of 7$7$ km the pilot will level the flight. We'll think of Earth's surface as flat for this hypothetical case. Once on level flight, continuing in the initial direction, what is the angle it is making to due east? Give your answer in degrees, but no units, only a number.