1. Ten school children are asked to stand in a line to wait for ice cream cones. A "line" in this case is a permutation because the order makes a difference. If
Raquel is first in line, that's different than being second or last. How many
different lines are possible for these 10 children?

How should the syntax in this sentence be changed, if at all? the scientists spent years analyzing the results of numerous medical studies meant to identify the cause of the disease. no change the scientists spent years looking at the results of a variety of different medical studies meant to locate the cause of the disease. the scientists spent years reviewing medical study results to find the cause of the disease. the scientists spent years studying the results of many medical studies in order to uncover the cause of the disease.