Explain why it is dangerous to burn a carbon-based fuel, such as propane or methane, in a closed room or building.

Forests and meadows are often cut down to make way for farms or large number of new homes. what are some of the elements of ecosystems that are lost when plants in these areas are removed?

20 pts ‼️ an unmanned spacecraft travels to mars. mars has a lower strength of gravity than earth. where in the image is the spacecraft’s weight the greatest?

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.