Stress response model
explained- :)))
Every seventh time a rat presses a lever, it receives food pallets.
Answer:
Buy Chapstick or use vaseline.
Explanation:
I used to live on a tropical island and I moved to the desert 6 years ago. Since it is so dry and my body is not used to it, I can't go 2 days without chapstick or my lips will become super chapped.