Does anyone know this question

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

Consider the first four terms of the sequence below. what is the 8th term of this sequence?

Drag the tiles to the boxes to form correct pairs. not all tiles will be used. match the circle equations in general form with their corresponding equations