Answer:
B: sample 4
Explanation:
This is because amino acids are basic units for proteins
Water Vapor and carbon dioxide
Answer:
Check if the rock layer has fossils in it.
Explanation:
The rock layer from the inside out and the fossils will tell you how old the rock is.
Answer:Cholecystokinin
Cholecystokinin stimulates the gallbladder to contract and release stored bile into the intestine.
Explanation:please give brainliest