Air pressure is caused by the air molecules around us. Air particles are always in random and continuos motion, bombarding each other in random direction. As air particles collide they create pressure.
Answer:
bees originally evolved from hunting wasps which acquired a taste for nectar and decided to become vegetarians. Fossil evidence is sparse but bees probably appeared on the planet about the same time as flowering plants in the Cretaceous period, 146 to 74 million years ago.
Explanation:
Your answer is correct. Chitin provide the strength to insect exoskeletons. Cellulose is the strength for plant. Starch and glycogen are energy sources for life.
Answer:
BRAIN??????
Explanation:
WHAT WAS THE LAST QUESTION>