(a) The scatter diagram below shows a relationship between two variables: X and Y. Identify if the plot indicates positive, zero, or negative correlation between the variables. (Mere statement will do, there is no need to comment or calculate.)

Y- 120 100 80 60 40 20 0

X-0 2 4 6 8 10 12 14 16

(b) The management of a chain departmental store would like to develop a model for predicting the weekly sales for individual stores based on the number of customers who made purchases. Using sales as the dependent variable, determine a simple linear regression equation for the data.

Number of customers Sales ($100) 15 2,500 20 3,510 50 8,750 40 6,520 63 10,700 10 1,850