PrepTest 134 · Section 2 · Question 7

Owen's Wagon and the Merry-Go-Round

Owen loaded his red wagon with rocks for the class garden. When he pulled, it barely budged at first, then slowly picked up speed. When he let go of the handle at the top of the slope, it kept rolling and slowed down bit by bit. 'Heavy stuff is lazy,' Owen said. 'Lazy to start, lazy to stop.' Then he pointed at the merry-go-round, packed with six kids. 'Same with that thing when it's full. Slow to spin up, slow to wind down.' Marcus nodded. 'So the merry-go-round has rocks in it.' Lulu wrote on her clipboard. 'No. Owen only said it acts similar. So all we know is that how full it is changes how fast it speeds up and slows down.' Priya sipped. 'Lunchbox Rule. Nothing extra.'

A wagon full of rocks is slow to get up to speed when pulled, and when it is let go it slows down gradually. A full merry-go-round behaves similarly: its load affects it the way rocks affect the wagon.

Which choice gets the best backing from the statements above?

The Case of the Crowded Ferry

The ferry company was sued for late arrivals. Mr. Whitfield called an engineer. 'A heavy barge takes a long time to get moving and a long time to stop,' she said. 'A ferry packed with passengers behaves the same way.' Ms. Tran pounced. 'So barges are making the ferry late?' 'No, ma'am. I said the ferry behaves similarly, not that barges cause anything.' The judge folded her hands. 'So the safe conclusion is that a ferry's load affects how quickly it speeds up and slows down.' 'Exactly, Your Honor. No more, no less.' The judge ruled that docking schedules must allow for full boats.