A retаil cоmpаny studies hоw mоnthly spending per customer (in dollаrs) depends on: the customer’s age (in years), and the customer’s number of store visits per month (Visits). Using a sample of customers, they obtain: Variable Estimate (β) Std. Error p-value Intercept 30.57 9.42 0.001 Age 0.01 0.24 0.954 Visits 8.47 2.08 < 0.001 Age × Visits 0.12 0.05 0.020