question: Two students each carry a box up to the third floor of a building. The total mass of each student and the box she is carrying is the same. Roberta makes the trip in 45 s while Mary takes 30 s. Which of the following statements best describes this task?
choices.text: Roberta does more total work than Mary. Mary does more total work than Roberta. Roberta has a greater power output than Mary. Mary has a greater power output than Roberta.
choices.label: A B C D