Help me answer this!!

Question

What is the cost (in dollars) of copper if you wish to cover your roof with 0.0125 inches of copper? The roof is 60.0 feet by 30.0 feet. The density of copper is 8.96 g/cm³. Copper cost $2.92 per pound. Report the correct number of significant figures.

Answer 1

Tailyn

All your data here has 3 significant figures so you will report your answer to that.

1 kg = 2.2 lbs

1 inch = 2.54 cm so a cubic inch is 2.54³ cm³

1 foot = 12 inches

Volume of copper in cubic inches = (60 x 12) x (30 x 12) x 0.0125

Volume in cubic centimetres = 2.54³ x 60 x 12 x 30 x 12 x 0.0125

Mass of copper in g = 8.96 x 2.54³ x 60 x 12 x 30 x 12 x 0.0125

Calculate the mass of copper in g, divide by 1000 to get in kg, multiply by 2,2 to get lbs, multiply by 2.92

Report the final answer here to 3 significant figures

Mike