What is the value of 6a + 13 if a=9

Describe the domain and range of y=2(3)^x-2+5

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?

Mr. rose asked his students to draw a quadrilateral with 4 unequal sides. draw an example of this kind of quadrilateral.