Given vectors A=(1i+7j−2k)N and B=(−1i−10j+13k)N, find the magnitude of resultant of these two vectors and angle that the resultant of these two vector makes with the z axis. IRI= N,
γ= °. pls help mangota​

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters