II. Find the sum of each of the following.
_____11. 4, 9, 14, 19, 24, … first 25 terms
_____12. -16, -20, -24, … first 20 terms
_____13. 10.2, 12.7, 15.2, 17.7, … first 10 terms
_____14. integers from 1 to 50
_____15. odd integers from 1 to 100