Which of these examples demonstrates homeostasis?
a. a bird flies south for the winter and flies back north in the spring.
b.
an amoeba takes in food and digests it.
c.
a cat runs away when it hears a noise.
d.
a person's body increases blood flow to its cold feet.

D)  A person's body increases blood flow to its cold feet
Homeostasis is when your body keeps a relatively stable internal temperature in order to stay healthy

It explains why rocks appear in layers

The rate that would change would be the  searching efficiency/attack rate. there are only two other rates in this model: the  growth rate of prey, and the  predator or consumer mortality rate.the  searching efficiency/attack rate is what indicates how effectively can a predator capture its prey whether in the searching process or actual capturing/attacking process.