1-Usually, errors are found in 10% of lines of code written by software engineers atError Free Code, Inc. What is the probability that in a randomly selected sample of 5 lines of code all of them have errors?

2- The probability that a train is behind the schedule for more than an hour is .0002. What's the probability that the train is behind the schedule for more than one hour twice a year (assume there are 365 days in a year)?

3- The probability of an eventA

Aoccurring in each of a series of independent trials is1/4. Find the probability of an eventA

Aoccurring twice in three trials.

4- Bob signed a document with a DSS signature. The probability that his signature is intercepted is (.1). Find the probability that at least one of three Bob's signatures is intercepted.