Answer:

Cost : The expenditure incurred by a producer on the factor as well as non-factor inputs for a given amount of output of a commodity.
The answer is C.
All your different body systems, (nervous system, digestive system, cardiovascular system, etc. ) all work together to maintain your internal environment, or the inside of your body! I hope this helps! :)
Answer:
4 I think
Explanation:
some elements are dangrous