Using the formula  c  = 2πr, find the circumference of a circle with diameter of 28 inches. round your answer to the nearest inch.                a.  44 in.      b.  56 in.      c.  88 in.      d.  28 in.

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