Mag and Direction of 3d Vectors

[Loppyfoot]

Homework Statement

Find the magnitude and direction of the following vectors.
C = -2 i - 9 j + 4 k



I found that the magnitude was 10. By using the square root of (4+9+4).

I don't know how to find:
Angle from +z-axis
and the direction in xy plane counter clockwise from the +x axis.

Thanks

 

[dtrain121]

gamma=Az divided by A

 

[Loppyfoot]

English please? is Az, 4k? Also, how do I find the direction in xy plane counter clockwise from the +x axis?