The mechanic does 4 oil changes in 2 hours. how many oil changes can the mechanic do in 8 hours?

What are the relative frequencies to the nearest hundredth of the columns of the two-way table? a b group 1 102 34 group 2 18 14

The number of potato chips in a bag is normally distributed with a mean of 71 and a standard deviation of 2. approximately what percent of bags contain between 69 and 73 potato chips? approximately 68% approximately 71% approximately 95% approximately 99.7%

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?