Which of the following statements about prescribed burns is true?a. Prescribed burns will always have detrimental effects on ecosystems, but should be used to protect homes. b.Prescribed burns are necessary for preventing natural wildfires. c.Prescribed burns can help maintain healthy ecosystems. d.None of the above

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.

Models are non-visual ways of coummincating how someone thinks about something in the natural world

Rarefaction is used for which of the following? a. creating a representative sample b. studying how disease impacts populations c. rediscovering species thought to be instinct d. determining which sea creatures live in an area