Need answer in html . thanks

1. Print 1 to 20 number using for loop. One below the other. 2. JavaScript program to find greatest of three numbers. Take 3 numbers from users and find the greatest of the three number. . 3. Print only even numbers from 1 to 20. 4. Take 3 marks as input from the user and calculate the average of the 3 subject marks and print the grade. If 90 and above - Agrade, 70 to 80 - B grade, 60 to 70-C grade, 50 - 60 -D grade and below 50 fail