Simplify: 2.3c – 5.25(2.6d – 2.8) – 7.9 a. 2.3c – 13.65d – 6.8 b. 2.3c – 13.65d + 6.8 c. 2.3c + 13.65d + 6.8 d. 2.3c + 13.65d – 6.8

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