David sold a $1.50 comic book to ronald. having no change for ronalds $5 dollar bill, david got the change at the store. he gave ronald the comic and $3.50. then the store owner told david that the $5 dollir bill was counterfeit. so david gave him five $1 bills. how much money did david make or lose is these transactions?

The price of an item has been reduced by 30%. the original price was $30. what is the price of the item now ?

How do you write 600 as a product of its prime factors (index! )

Assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.