How do u simplify the following expression by combining like terms?

Expression: 3v + 7v + 9v =

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

Find the slope and the y-intercept if there's one and the equation of the line given these two points( 3, 2) and( 3, -4)

East black horse $0.25 total budget is $555 it'll cost $115 for other supplies about how many flyers do you think we can buy