During which period did rodents, marsupials, primates, and hoofed animals first appear in north america

For the answer to the question above, I believe the answer is "Tertiary Period"
The Tertiary Period marks the beginning of Cenozoic Era. It only began 65M years ago and lasted more than 63M years, until 1.8 million years ago. I hope my answer helped you. Have a nice day!

From our previous experiment, we examined how many drops a penny can hold - and place drops of salt water on the penny after recording 5 trials each, take the average of each solution.