The coins (UsingR) dataset describes coins in the author's change bin with year and value. Do not use explicit loops for any calculations. Do not hard code the denominations in the solution. The solution should work for any denominations. a) How many coins are there of each denomination? b) What is the total value of the coins for each denomination? c) What is the total value of all the coins made year 2002? d) Show the barplot for the total value of coins by year

Write a grading program for a class with the following grading policies: a. there are two quizzes, each graded on the basis of 10 points. b. there is one midterm exam and one final exam, each graded on the basis of 100 points. c. the final exam counts for 50% of the grade, the midterm counts for 25%, and the two quizzes together count for a total of 25%. (do not forget to normalize the quiz scores. they should be converted to a percentage before they are averaged in.) any grade of 90 or more is an a, any grade of 80 or more (but less than 90) is a b, any grade of 70 or more (but less than 80) is a c, any grade of 60 or more (but less than 70) is a d, and any grade below 60 is an f. the program will read in the student’s scores and output the student’s record, which consists of two quiz and two exam scores as well as the student’s average numeric score for the entire course and final letter grade. define and use a structure for the student reco