These answers aren´t valid .
The correct answer will be:
Planetary system.
D. Circulatory
The digestive system works very closely with the circulatory system to get the absorbed nutrients distributed through your body. The circulatory system also carries chemical signals from your endocrine system that control the speed of digestion.
The total amount of energy always stays the same because of the law of conservation of energy, meaning that there is always the same amount of energy, it just gets turned into different forms like potential energy, kinetic energy, sound, thermal, etc.
The correct answer is this one: "D) significantly more than 100 billion gallons ." Clouds dump around 100 billion gallons of water on rainforests each year. The amount of rain is evaporated from the rivers, lakes and surface of rainforests each year is significantly more than 100 billion gallons<span> </span>
A: Human Body
C is wrong because they don’t have the tools to test it on another planet
