6 Computer breakdowns occur randomly on average once every 48 hours of use.
- Calculate the probability that there will be fewer than 4 breakdowns in 60 hours of use.
- Find the probability that the number of breakdowns in one year (8760 hours) of use is more than 200.
- Independently of the computer breaking down, the computer operator receives phone calls randomly on average twice in every 24 -hour period. Find the probability that the total number of phone calls and computer breakdowns in a 60-hour period is exactly 4 .