6-C (breaks off)
7-C(they secrete acid that breaks away rocks)
The bronchi are where air passes from the trachea.
Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.
Answer:
Thomas Robert Malthus (born 1766) was a British Reverand and Scholar,. He was nfluential in Political Economy and Demography. Between 1798 and 1826 Malthus published six editions of his famous treatise. THOMAS wrote a book called "AN ESSAY ON PRINCIPAL OF POPULATION." He became known for his theories on population and factors on population growth.
Explanation:
You could have made sure the books were the same weight and your friends could have done it at the same time as you
