2b + 7z when b = 3, z = 4. please show your work and make sure you get the answer right thank you

Three coins are flipped. what is the probability that there will be at least two tails?

Which graph represents the parent function of y=(x+2)(x-2)

The stem-and-leaf plot shows the heights in centimeters of teddy bear sunflowers grown in two different types of soil. soil a soil b 5 9 5 2 1 1 6 3 9 5 1 0 7 0 2 3 6 7 8 2 1 8 3 0 9 key: 9|6 means 69 key: 5|8 means 58 calculate the mean of each data set. calculate the mean absolute deviation (mad) of each data set. which set is more variable? how do you know?