Question 1 A program converts student marks that are input as marks out of 100 to letter grades following the rules below: mark of at least 90 earns A+ mark of at least 80 earns A mark of at least 70 earns B mark of at least 60 earns C mark of at least 50 earns D mark below 50 means F (Fail) Note: Numeric marks are recorded accurate to one decimal point (0.1) and should be rounded up to the nearest whole number (0.5+1) by the grading program. The objective of testing is to ensure that students are assigned the correct grade, given their numeric mark i. Find equivalence classes (EP) for all input of the specification. ii. Find boundary values for all input of the specification by using BVA. You can use a time line or just state the possible values. iii. Identify how many test cases to cover 100% test coverage for your answer in (i) and (ii). iv. Write all possible test cases for your answer in (i) and (ii)