Rearrange the events into chronological order. Place the first event to occur at the top and the last event to occur at the bottom. Gases from Earth's surface form the atmosphere.
Earth's surface cools.
Photosynthetic organisms absorb atmospheric carbon dioxide and release oxygen.
Organisms with aerobic metabolism evolve.
The composition of Earth's atmosphere changes.

What was dr. willem johan kolff’s first step in using the scientific process to invent the hemodialysis machine? he built the machine and tried it with various patients, collecting data about its effectiveness. when a patient’s kidneys failed, he wondered if it would be possible to perform kidney functions with an external machine. he researched and collected data about numerous patients who exhibited symptoms of kidney failure. he drew conclusions from studies of various symptoms of kidney failure, and drew a design for the ideal external blood-processing machine.

Biomass can be used to generate electricity. biomass relies heavily on agricultural crops. plants release carbon dioxide and water in combustion. plants use photosynthesis to originally generate the energy that is needed. the chemical energy of these plants all started with what energy source?

The breakdown of food is accomplished by enzymes. a. physical b. chemical c. mechanical d. none of the above