Joaquim wants to estimate the number of hairs on his head. He does some research and finds that, on average, people have about 300 hairs per cm2. He decides that half of a soccer ball is roughly equivalent to a person’s scalp area. If an official size 5 soccer ball has a radius of 11 cm, which is the most reasonable estimate for the number of hairs on his head? A. 3 × 107 hairs
B. 3 × 105 hairs
C. 3 × 104 hairs
D. 3 × 103 hairs
E. 3 × 106 hairs

17. a researcher measures three variables, x, y, and z for each individual in a sample of n = 20. the pearson correlations for this sample are rxy = 0.6, rxz = 0.4, and ryz = 0.7. a. find the partial correlation between x and y, holding z constant. b. find the partial correlation between x and z, holding y constant. (hint: simply switch the labels for the variables y and z to correspond with the labels in the equation.) gravetter, frederick j. statistics for the behavioral sciences (p. 526). cengage learning. kindle edition.

How do you solving the solution of each system using elimination?

If i have 20$ and i gave 5$ away how much i got