Given that sin63= 0.891 enter the cosine of a complementary angle

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

Rectangle bcde is similar to rectangle vwxy. what is the length of side vy? a) 1 7 b) 2 7 c) 3 7 d) 4 7

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