Answer
(a) 1000
(b) 0.001
(c) 0.999
Work Step by Step
number of possible access codes = 10^{3} = 1000
Probability of randomly selecting the correct access code on the first try = 1/1000
= 0.001
probability of not selecting the correct access code on the first try = 1 - 1/1000 = 0.999
