(Solved): discrete math application of number theory D. Applications of Number Theory 1. Hashing function is o ...

D. Applications of Number Theory 1. Hashing function is one of the applications of congruences. For example, in the Social Security System database, records are identified using the Social Security number of the customer as the key, which uniquely identifies each customer's records. A hashing function h assigns memory location h(k) to the record that has k as its key. One of the most common hashing function is h(k)= k mod m where m is the number of available memory locations. Which memory location is assigned by the hashing function h(k)= k mod 97 to the record of a customer with Social Security number 501338753? 2. Caesar cipher is another application of congruence. To encrypt messages, Julius Caesar replaced each letter by an integer from 0 to 25 equal to one less than its position in the alphabet. For example, replace A by 0, K by 10, and Z by 25. Caesar's encryption method can be represented by f(p) = (p + 3) mod 26 where p is the integer mentioned in the previous statement. Lastly, the numbers are translated back to letters. a) Encrypt the message, "STOP POLLUTION", using Caesar cipher. b) Decrypt the message, "EOXH MHDQV", which was encrypted using Caesar cipher.