B. Because of the presence of hydrogen sulphide in Brass, it combines with oxygen in air and form water, evaporates. So remained sulphide is colourless in air .So Brass gets discoloured in the air.
Answer:
The organisms at the base of the food chain are photosynthetic.
Explanation:
Answer: The answer would be Substrates
What kind of force? There are lots of forces acting on the car at this point.
B oxygen because they need it to survive