Your school is in a safe neighborhood, but there have been a few thefts at atms. you work part-time in your school's campus security office and have been asked to prepare tips for students about atm safety. thieves can capture a credit card number by placing a(n) on an atm.

The answer is: skimmer

Skimmer is an additional card reader that is placed on top of the ATM's Card slot. When you put your ATM card into that slot, the skimmer would read the credit card number that exist on the card.  The skimmer usually accompanied by a small hidden camera that can capture  the movement of your fingers on the ATM keypad.  Having both would make it possible for the thieves to take the money from your account.

answer; overt behavior;