Final answer:
If you find an infant who is unresponsive, not breathing, and without a pulse, the next action you should take is to activate EMS while performing CPR.
Step-by-step explanation:
If you find an infant who is unresponsive, not breathing, and without a pulse, the next action you should take is to activate EMS (Emergency Medical Services) while performing CPR. CPR (cardiopulmonary resuscitation) helps maintain blood flow to the brain and other vital organs until medical professionals arrive. The recommended steps for CPR include compressing the chest at least 5 cm deep and at a rate of 100 compressions per minute. This should be done continuously until the baby regains consciousness or medical help arrives.