Answer:
a) inhalation and exhalation
b)
c) oxygen....gets rid of carbon dioxide
d) Vagus reflex (?)
e) Respiratory System
f)
g) oxyhemoglobin
h) iron
i) carbonic acid
j) the blood to the lungs.
k) diaphragm muscle
Sorry I don't know what the correct answer to b) and f)
Your answer is C: 2 billions years! Hope that helps!
Answer:
they keep the airways clear of mucus and dirt, allowing breathing to be easy and without irritation
Explanation:
The best answer is (1)
Fossil fuels are commercially available as an energy source.
They are very easy to find. More and more extractions of fossil fuels is going on everyday. With advancement in science and technology, the refineries and extraction procedures have improved a lot. This makes their availability even better.
Fossil fuels are also easily combustible. Most combustion engines need to be powered with little amount of fuel to produce large amount of energy. Very large amounts of electricity can be generated from fossil fuels.
The consumers are mostly affected secondary consumers.
Please mark me as brainlest.
