My sum of ones digit and tens digit is also 10 however, my ones digit is greater than my tens digit. i am a prime number less tha 30 what number am i?

Suppose you are choosing a 6-digit personal access code. this code is made up of 4 digits chosen from 1 to 9, followed by 2 letters chosen from a to z. any of these digits or letters can be repeated. find the total number of personal access codes that can be formed. 492,804 341,172 39,917,124 4,435,236