Can someone please help me answer this question for this situation?

Customers at Walmart have a choice when paying for their groceries. They may check out and pay using the standard cashier-assisted checkout, or they may use the self-checkout. In the standard checkout, a Walmart employee scans each item and puts it on a short conveyor, where another employee puts it in a bag and then into the grocery cart. In the self-checkout lane, the customer scans each item, bags it, and places the bags in the cart him- or herself. The self-checkout lane is designed to reduce the time a customer spends in the checkout line. One Walmart store manager would like to know if the mean checkout time using the standard checkout method is longer than using the self-checkout lane.

Reference:

Source: Lind, D. A., Marchal, W. G., & Wathen, S. A. (2015).Statistical techniques in business & economics(16th ed.). New York, NY: McGraw-Hill/Irwin.

What data should the manager collect for the hypothesis test? Should the manager conducthypothesis tests of two populations' means for independent samples, or dependent samples? Please explain.