There are 34 learners in a Grade 9 class. The class register shows that there are 4 more girls than boys.
How many boys are there in the class?​

Pls , the question is in the picture!

Is triangle jkl congruent to triangle rst? if so, what is the scale factor?

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?