Which expression will be easier to simplify if you use the associative property to change the grouping

7+ 2[(5^2)*152%]= answer as soon as you can

Agreeting card company can produce a box of cards for $7.50. if the initial investment by the company was $50,000, how many boxes of cards must be produced before the average cost per box falls to $10.50?

Ahiking trail is 6 miles long. it has 4 exercise stations, spaced evenly along the trail. what is the distance between each exercise station?