Here are the answers to the questions based on the passage:

**Question 13:** What is the main idea of the passage?
**Answer:** C. Carbon footprints and ways to reduce them.

**Question 14:** According to the passage, what is a carbon footprint?
**Answer:** A. the amount of carbon dioxide that we produce through our activities.

**Question 15:** Which of the following is TRUE according to the first paragraph?
**Answer:** A. Our daily activities can increase the carbon footprint.

**Question 16:** The word "them" in paragraph 2 refers to
**Answer:** B. devices.

**Question 17:** The phrase "appliances" in paragraph 2 is closest in meaning to
**Answer:** A. devices.

**Question 18:** According to the passage, which of the following is NOT mentioned?
**Answer:** D. Recycling means that we reuse the materials.

**Question 19:** The word "take in" in the final paragraph is opposite in meaning to
**Answer:** A. absorb.

**Question 20:** Which of the following is NOT TRUE according to the passage?
**Answer:** D. Eating meat is better for the environment than eating vegetables.

**Extra Question:** It can be inferred from the last paragraph that
**Answer:** A. recycling reduces energy productions and CO2 emissions.

If you have more specific questions or need further assistance, let me know!