Kevin is an auto mechanic. He spends 3 hours when he replaces the shocks on a car and 2 hours when he replaces the brakes. He works no more then 42 hours a week. He routinely completes at least 4 shocks replacements and 6 brake replacements a week. If he charges $400 for labor replacing shocks and $300 for replacing brakes, how many jobs of each type should he complete a week to maximize his income?

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?

Anyone know these questions? i need ,.

Solve the system of equations using the substitution method. {y=−3x+7x=−2y−16 enter your answers in the boxes.