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There are 12 boy and13 girls in a class. if the teacher randomly chooses a student’s name out of a hat what is the probability it will be a girl

Question 5 of 10 2 points if a population is a sample of the population could be a. registered voters; all citizens o o b. baptists; all religious people o c. people who purchased shoes; all customers o d. the entire school faculty; math teachers

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?