Answer:
because of factories and cars and smoking
Explanation:
Answer:
They fall from the clouds as ice crystals.
They form around particles in the atmosphere.
They form when water vapor is converted directly to ice crystals.
Explanation:
The function of protein that helps chemical react is catalyzing
Answer:
The Circulatory System
Explanation:
When blood is rich in carbon dioxide it leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs. (All of which have to do with the circulatory system)
Answer:
Deuterium, (D, or 2H), also called heavy hydrogen, isotope of hydrogen with a nucleus consisting of one proton and one neutron, which is double the mass of the nucleus of ordinary hydrogen (one proton). Deuterium has an atomic weight of 2.014
Explanation:
