It's been a while but I believe it's C. Supply and Demand would fluctuate the prices.
Answer:
is chemical compound with the symbol n
Answer:
You can clearly see the spring that makes the pointer rise or fall as the pressure changes. ... A spring is cunningly attached to the box and, as the box moves in and out in response to the changes in air pressure, the spring expands or contracts and moves the pointer on the dial.......i'm going to say C
1836.......................
