On a standardized exam, the scores are normally distributed with a mean of 145 and a standard deviation of 25. Find the z-score of a person who scored 85 on the exam.

Acoin is tossed twice. let e e be the event "the first toss shows heads" and f f the event "the second toss shows heads". (a) are the events e e and f f independent? input yes or no here: yes (b) find the probability of showing heads on both toss. input your answer here: preview

Find the solutions for a triangle with a =16, c =12, and b = 63º

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny