4+4+4+6+6=24 Hours
15+15+20+20+20= 1 Hr 30 Min
24+1= 25 Hours + 30 Minutes=
Final answer: C) 25 hours and 30 minutes
The cross product of two vectors gives a third vector
that is orthogonal to the first two.
Normalize this vector by dividing it by its norm:
To get another vector orthogonal to the first two, you can just change the sign and use
.