I'm not 100% sure, but I'd say the availability of vaccines and medicine.
Answer:
An arterie is a vessel that carries blood away from the heart, and a vein carries blood to the heart
Explanation:
Mark as barinly plzzz :))))
Answer:
B. The carbon cycle
Explanation:
In the carbon cycle, carbon in the atmosphere is absorbed into plants, where the plants use photosynthesis to convert that carbon into oxygen and energy for themselves. Neither of the other cycles involves a plant taking in a gas directly from the atmosphere.
Hopefully this was helpful! :)
The answer is red for the highest surface temp of a star.
The simplest organisms are cells.
A cell is: The smallest structural and functional unit of an organism.