Scouting troops in Franklin county are putting on a crab feed to raise money for camp. They offer a complete crab dinner as well as a vegetarian option. One troop member sold tickets for 19 crab meals and 9 vegetarian meals, with the total receipts of $965. Another sold tickets for 19 crab meals and 24 vegetarian meals, bringing in a total of $1370. How much do the two types of tickets cost?

Assume that there is a 11% rate of disk drive failure in a year. a. if all your computer data is stored on a hard disk drive with a copy stored on a second hard disk drive, what is the probability that during a year, you can avoid catastrophe with at least one working drive? b. if copies of all your computer data are stored on four independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?