Explanation:
it is systematic desensitization.
Answer:
for 16 it is heart.
Explanation:
for 17 it is kidney to bladder
Answer:
Without an oxygen atmosphere very few things could live on the early Earth. Anaerobic bacteria were probably the first living things on Earth. The early Earth had no oceans and was frequently hit with meteorites and asteroids.
Explanation:
Hydrogen, for example, it gives trees inter molecular force.
