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Steven and Joey are sent to the main office to pick up materials fo science class. Steven picks up a box that contains 40.0g of styrofoam. Joey picks up a box that contains 40.0g of marbles. On the way back to class, the boys begin to argue over whose bo is heavier. Steven thinks he has the heavier box. Joey thinks his box is definitely heavier than Steven's. 1. Which boy is correct? EXPLAIN!!!!​