Each statement best explains why it is more difficult to use coal versus other alternate source of energy except: 1. Coal produces more pollutants in the air.

2. It is more difficult to mine for coal than other minerals.

3. Coals are not commonly used because it is more difficult to burn.

4. Coals are not commonly used because it produces more negative impact to the environment.

Coal produces more pollutants in the air.

Explanation:

Each other answer has the words 'more difficult' or 'not commonly used.   I think this is right...I won't see my grade for a long time though very, truly sorry if it is wrong! :)                                                                                          

explanation:

since this is put under health, i would define "ethical (medical) behavior" the way the oath for doctors is recited.   "first do no harm."

but the term in general means when given a choice between right and wrong, we should always choose right. if we do, then we are practicing ethical behavior.

(b) which contains higher levels of vitamin b, oranges or spinach?

explanation:

you can eliminate a, c, and d because they are questions based on opinions.