The right subject for this question is physics.
To calculate the work you use the formula:
Work = force * displacement
Work = 2500 pounds * 30 feet = 75,000 pounds - feet
To calculate the power you use the formula:
power = work / time
Power = 75,000 pound - feet / 30 seconds = 2300 pound-feet / second.
Answer:
The balanced molecular equation for the reaction :

Explanation:
The reaction between copper(II) nitrate and potassium carbonate gives solid precipitate of copper(II) carbonate and aqueous solution of potassium nitrate.

According to reaction, 1 mole of copper(II) nitrate reacts with 1 mole of potassium carbonate to give 1 mole of copper(II) carbonate and 2 moles of potassium nitrate,
The Answer for this question is : A
1 & 2
Yes they can have origins in nature. A bunch of the elements on the periodic table are chemicals and this are basic substances and cannot be man made.
Correct me if I wrong but I think it's "c"