The students in science class spent 65% of the class period performing an experiment. how long is the class period if the time spent on this was 52 minutes

An advertising firm has an old computer that can prepare a whole mailing in 6 hours. with the of newer model the job is complete in 2 hours. how long would it take the newer model to do the job alone?

What is the prime factorization of 23 ?me with this question

What is the range? can’t seem to find it out