What expression would represent the difference in the total number of cubic yards the first truck delivers compared to the second

Your friend swims on the school team. in his first four races, his times are 24.7, 23.5, 25.6, and 27.2 seconds. which time listed for his next race would make the range larger?

If square root x = -7, then x= -49 true or false

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much