List grade points by letter grade?
select gradepoint,lettergrade from gradeconversion
List max of each grade for all letter grades?
select max ( gradepoint ) from gradeconversion
The max for each letter grade?
select lettergrade, max ( gradepoint ) from gradeconversion group by lettergrade
List the min grade point for each letter grade?
select min ( gradepoint ), lettergrade from gradeconversion group by lettergrade
Find the min grade point for all letter grade?
select min ( gradepoint ) from gradeconversion
Find the max and min grade point for all letter grade?
select max ( gradepoint ), min ( gradepoint ) from gradeconversion