Answer:
ATP
Explanation:
ATP is a chemical forumal for enegry
A contour interval is the lines on a topographic map that state the height (from sea level) of the hill, valley, mountain or the ground level.
The answer to this question is the second option
The accumulation of several mutations in the main gene on the virus's surface may be able to give H7N9 the ability to spread like human flu viruses do, passing from person to person through coughing and sneezing.
