Arocket is 1 mile above the earth in 30 seconds and 5 miles above the earth in 2.5 minutes. what is the rockets rate of change in miles per second? what about miles per minute.

The constant rate of change is 30 seconds because:
1 mile=30 seconds
2 miles=1 minute
3 miles=1 minute and 30 seconds
4 miles=2 minutes
5 miles=2 minutes and 30 seconds 
or in other words 2.5