Are physical properties only observable by destroying the substance?

Which of the following is an example of how telecommunication devices people do their jobs? a.) a security guard checks the time using a digital watch. b.) a banker does some quick math using a solar calculator. c.) a nurse uses a digital thermometer to take a patient’s temperature. d.) a construction worker reports in to his office using a cell phone.

The total amount of fresh water on earth is estimated to be 3.73 x 10^8 km^3. what is this volume in cubic meters? in cubic feet?

If 15.6 grams of iron (iii) oxide reacts with 12.8 grams of carbon monoxide to produce 9.58 g of pure iron, what are the theoretical yield and percent yield of this reaction? be sure to show the work that you did to solve this problem. unbalanced equation: fe2o3 + co yields fe + co2