How many terms are in the algebraic expression 3x^2 + 4y - 1

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.

How do you figure out which order to do two step equations in? like which thing do you subtract/add/multiply/divide first? i understand that you do the opposite of whatever's shown on the opposite side, but when?

The probability of drawing a heart from a standard deck of cards is .25. you record the card you draw and return the card before shuffling to ensure a binomial distribution. if you do this 20 times what is the probability that you will draw a heart 7 times? a. 0.888 b. 0.001 c. 0.112 d. 0.473