l need the formula for grade from rank,

The table below shows the scores in three different sections of a class. Given the data below, answer the following questions. A - Sort the data by score in descending order and assign each student an overall rank so that the student with the highest score in the class is ranked 1 and the student with the second highest score is ranked 2, etc. Students with the same score should get the same rank and students with a score below should be ranked 1 below. For instance, if you had the scores 90, 87, 87, 85, the ranks should be 1, 2, 2, 3, not 1, 2, 2, 4. (Hint: With the data sorted, you can do this using an IF function) B - Assign everyone a grade based on their score using the scoring rules listed in the "Grade Rules" table. C - You decide you don't like the grade distribution, so instead you decide to give everyone a grade based on their rank. You decide to give students ranked in the top 15 an A, students not in the top 15 but in the top 108 a B, students not in the top 108 but in the top 172 a C, students not in the top 12 but in the top 212 a D, and everyone else an F. D - In the "Counts" table, count the number of students who fall into each section and "Orade from Rank" combination. Section Student Score Grade Rules Counts Section Grade Count 98.6 96.9 1 A 96 Overall Grade from Grade from Rank Score Rank 1 A 2A 3 A 4 A 5 A 6 A 7A 8 A 9B 0 to 59.99 F 60 to 69.99 D 70 to 79.99 C 80 to 89.99 B 90 to 100 A 1 B 1 C 1 D 1 F 2 A 2 B 20 10 B 2 D 1 Gloria Wright 1 Chris Howard 1 Ronda Tolbert 1 Cody Flores 1 Marcella Weaver 1 Katherine Morris 1 Chester Dawson 1 Benny Wade 1 Carl Bryant 1 Gloria Sanchez 1 Adam Cooper 1 Herman Hunt 1 Ralph Long 1 Anna Williams 1 Judith Sanders 1 Jason Johnson 1 Kristina Mendoza 1 Ruben Zimmerman 1 Wenona Coons 1 Julia Roberts 94.6 94.3 93 91.7 90.7 89.6 89.4 88.6 87.4 87.2 86 85.7 85.2 84.9 11 B 12 B 13 B 14 B 2 F 3 A 3 B 3 C 15 B 3D 3 F 16 B 17 B 84.9 17 B 18 B 84.3 83.2 19 B