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1. Create a Java program that prompts the user to enter an integer and then displays the integer with its digits reversed. The output must also include leading zeros, such as displaying 5000 as 0005 and 980 as 089. Your program should not convert the integer to a string or use any build-in libraries; it should only use integer operations. 2. Develop a Java program that reads a set of exam scores from the user. The program must count and display the number of outstanding scores (between 90-100), the number of satisfactory scores (between 60-89), and the number of unsatisfactory scores (between 0-59). The input process must stop when the user enters an exam score of 1. For example, given the input values 95,78,72,55,91, and -1, the output should be: Outstanding 2 Satisfactory 2 Unsatisfactory 1 3. Abdullah, a public figure on social media, is promoting a restaurant on his page. He is conducting a photo contest in which followers can post photos taken at the restaurant. For each 100 likes, the follower will receive a free piece of cheesecake. Write a Java program that prompts the user to enter the follower's username and the number of likes received for their photo. The program should then display the follower's username followed by a hash symbol (\#) for each free piece of cheesecake earned. The program should perform this operation for 10 followers. For example, if the input is Ali 500, then the output must be Ali \#HAtIH, while if the input is Suha 50. then the output must be Suha. Note that, no \# was displayed next to Suha since the value is below 100