When you have the bottom measurement of the triangle (base) and the height of the triangle in the center, you multiply them together and then divide by 2.
~Do you need more explaining~?
Answer: D. test tubes, thermometers, etc
I think this is the correct answer. Sorry if it is not.
Explanation:
M=f/a m=129000N/84m/s/s=1535.714286kg/m/s/s