Find slope: PLEASE HELP !

Keith bought a soft drink for 4 dollars and 9 candy bars .he spent a total of 31 dollars .how much did each candy bar cost?

An eight-sided die, which may or may not be a fair die, has four colors on it; you have been tossing the die for an hour and have recorded the color rolled for each toss. what is the probability you will roll a brown on your next toss of the die? express your answer as a simplified fraction or a decimal rounded to four decimal places.

Which representation has a constant of variation of -2.5