The subject is Perl Scripting. Can someone please help me? Padre is the software I use. Please include comments throughout to show what each thing does.

Computer-Assisted Instruction: Programming Exercise: Write a program to allow the user to pick a type of arithmetic problem to study. An option of 1 means addition problems only, 2 means subtraction problems only, 3 means multiplication problems only, 4 means division problems only and 5 means random mixture of all these types. (Computer-Assisted Instruction) The use of computers in education is referred to as computer-assisted instruction (CAI). Write a program that will help an elementary school student learn arithmetic operations. Use a Random object to produce two positive one-digit integers. The program should then prompt the user with a question, such as How much is 6 times 7? The student then inputs the answer. Next, the program checks the student's answer. If it's correct, display the message "Very good!" and ask another multiplication question. If the answer is wrong, display the message "No. Please try again." and let the student try the same question repeatedly until the student finally gets it right Modifying Exercise: (Computer-Assisted Instruction: Reducing Student Fatigue) One problem in CAI environments is student fatigue. This can be reduced by varying the computer's responses to hold the student's attention, so that various comments are displayed for each answer as follows: Possible responses to a correct answer: Very good! Excellent! Nice work! Keep up the good work! Possible responses to an incorrect answer: No. Please try again. Wrong. Try once more. Don't give up! No. Keep trying Use random-number generation to choose a number from 1 to 4 that will be used to select one of the four appropriate responses to each correct or incorrect answer. Use a switch or if statement to issue the responses. Modifying Exercise (Computer-Assisted Instruction: Monitoring Student Performance) More sophisticated computer-assisted instruction systems monitor the student's performance over a period of time. Count the number of correct and incorrect responses typed by the student. After the student types 10 answers, your program should calculate the percentages that are correct. If the percentage is lower than 75%, display "Please ask your teacher for extra help.", then reset the program so another student can try it. If the percentage is 75% or higher, display "Congratulations, you are ready to go to the next level!", then reset the program so another student can try it. Computer-Assisted Instruction: Programming Exercise: Write a program to allow the user to pick a type of arithmetic problem to study. An option of 1 means addition problems only, 2 means subtraction problems only, 3 means multiplication problems only, 4 means division problems only and 5 means random mixture of all these types. (Computer-Assisted Instruction) The use of computers in education is referred to as computer-assisted instruction (CAI). Write a program that will help an elementary school student learn arithmetic operations. Use a Random object to produce two positive one-digit integers. The program should then prompt the user with a question, such as How much is 6 times 7? The student then inputs the answer. Next, the program checks the student's answer. If it's correct, display the message "Very good!" and ask another multiplication question. If the answer is wrong, display the message "No. Please try again." and let the student try the same question repeatedly until the student finally gets it right Modifying Exercise: (Computer-Assisted Instruction: Reducing Student Fatigue) One problem in CAI environments is student fatigue. This can be reduced by varying the computer's responses to hold the student's attention, so that various comments are displayed for each answer as follows: Possible responses to a correct answer: Very good! Excellent! Nice work! Keep up the good work! Possible responses to an incorrect answer: No. Please try again. Wrong. Try once more. Don't give up! No. Keep trying Use random-number generation to choose a number from 1 to 4 that will be used to select one of the four appropriate responses to each correct or incorrect answer. Use a switch or if statement to issue the responses. Modifying Exercise (Computer-Assisted Instruction: Monitoring Student Performance) More sophisticated computer-assisted instruction systems monitor the student's performance over a period of time. Count the number of correct and incorrect responses typed by the student. After the student types 10 answers, your program should calculate the percentages that are correct. If the percentage is lower than 75%, display "Please ask your teacher for extra help.", then reset the program so another student can try it. If the percentage is 75% or higher, display "Congratulations, you are ready to go to the next level!", then reset the program so another student can try it