You're using an unreliable Wi-Fi connection. You send three emails - one to your bank, one to magazine, and one to your professor. Each email has a 30% chance of going through, independently of whether other emails go through.
a) Determine the chance that all three emails go through?
b) Determine the chance that the emails to the bank and magazine go through but not the one to your professor?
c) Determine the chance that exactly two emails go through?