Bacteria are used by humans for which of the following purposes?
a. bioremediation
c. recycling
b. producing insulin
d. all of the above

The answer is D. Bacteria has been used for bioremediation in order to degrade contaminants. It was also used for recycling various materials already, and even other substances. Some even used certain microorganisms in order to generate insulin, and a lot of research papers have proven that.

B. Producing Insulin
In biotechnology, bacteria are mostly used for making substances for the welfare of Mankind. Mostly biotechnologists use bacteria for producing insulin by different biotechnological methods.

1) the mayans built pyramids just like the egyptians. the mayans also used hieroglyphics like them.2) power was passed down by family. for example, if the father dies, the son would be the next king.3)they both built pyramids for their structures.4)the main crop for the mayans was maize.5)they also grew manioc, beans,  squash,  amaranth, and chile peppers.