Melissa worked to earn $20.00. Alan worked for $12.00 hours. If she earns $2.00 per hour, how many hours did Melissa work?

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.

Find the roots of the polynomial function f(x) = x^3 + 2x^2 + x

If you are dealt 4 cards from a shuffled deck of 52? cards, find the probability that all 4 cards are diamondsdiamonds.