Answer: b
Explanation: b best fits how the transmission of hiv works
What causes people to be color-blind
can be tested scientifically
As newer rock layers form, they overlap with the ones with the pre-existing ones. Therefore, when looking for older rock layers, we would look for the ones that are deeper beneath the surface of the earth. On the other hand, newer rock layers are found at the top. This is also observed in the fact that oil rigs dig very deep into the ground to access the layers that are millions of years old.
Answer:
B: sample 4
Explanation:
This is because amino acids are basic units for proteins
