Dwayne wants to buy a jump rope that costs $4, a board game that costs $7, and a playground ball that costs $3. He has saved $9 from his allowance, and his uncle gave him $4. How much more money does Dwayne need to buy the jump rope, the game, and the ball?

What is the volume of this square pyramid?

Need on this geometry question. explain how you did it.

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