What is the circumference of all of these

The equation of a circle is (x + 4)2 + (y + 6)2 = 16. determine the length of the radius. 10 4 16 8 my flower basket delivers flowers within a 20 mile radius of their store. if this area is represented graphically, with my flower basket located at (5, 2), what is the equation that represents the delivery area? (x - 2)2 + (y - 5)2 = 20 (x - 5)2 + (y - 2)2 = 20 (x + 5)2 + (y + 2)2 = 400 (x - 5)2 + (y - 2)2 = 400

For what value of (y) is 3^3/3^y =1/9

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