B. is the answer i really hope i helped please mark as brainliest.
Its Light because it reacts to photosynthesis
Answer:
List the features of gas exchange surfaces in animals.
1)They are moist to prevent the cells from drying and to allow gases to dissolve;
2)They have a large surface area , so that a lot of gas can diffuse across at the same time;
3)They have a high concentration gradient - maintained by the movement of air & blood.
To get an average, you must add all of the numbers together, and divide that sum by the amount of numbers there are. There are 6 number, which is what we must divide by.
6.8g is the average for the set of measurements.