Read the sentence from the passage.
"Outfitted in their 'bathing suits' and suspended on a mechanical wave simulator that moves them in circles, the
turtles 'swim' - without any water!" (paragraph 16)
What does the word simulator mean as it is used in the sentence?
. a method used for tracking
a machine used for imitation
a device used for encouragement
a tool used for long-distance transportation
