Final answer:
The sales manager at the car dealership is using the influence tactic of coercion.
Step-by-step explanation:
The sales manager at a large car dealership is using the influence tactic of coercion.
Coercion is a form of influence where a person uses threats, punishment, or negative consequences to get others to comply with their demands or expectations. In this case, the sales manager is using the threat of termination ('you're history') to motivate the sales staff to meet their sales quota.
By using this influence tactic, the sales manager is attempting to create a sense of fear or pressure among the sales staff, hoping that it will drive them to achieve their sales goals.