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sertanlavr [38]
3 years ago
13

A humor piece in a reputable medical journal notes that people can't tell for sure whether parachutes are safe and effective be

cause there has never been a properly randomized, double-blind, placebo-controlled study of parachute effectiveness in skydiving. Suppose a researcher were designing such a study.
Complete parts 1 and 2 below.

1)What is the factor in this experiment?

A. Jumping with or without a parachute
B. The parachutes
C. How the parachutes are distributed to the skydivers
D. The skydivers

2) What experimental units should be used?
A. Different brands of parachutes B. Airplanes
C. Volunteer skydivers
D. The research team
Biology
1 answer:
dmitriy555 [2]3 years ago
6 0
The parachutes are the subject of the study and different types, or brands, of them should be used.
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What is the rapid change in a membrane's potential caused by the depolarization of a neuron?
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During depolarization, the membrane potential rapidly shifts from negative to positive. As the sodium ions rush back into the cell, they add positive charge to the cell interior, and change the membrane potential from negative to positive.

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valkas [14]

Answer:

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Explanation:

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2 years ago
complex chemical processes such as photosynthesis occur in a controlled series of steps with the help of ?
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Chlorophyll and sun light.

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Photosynthesis:

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water is supplied through the roots, carbon dioxide collected through stomata and sun light is capture  by chloroplast.

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6H₂O + 6CO₂ + energy  →   C₆H₁₂O₆ + 6O₂

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What protects and nourishes a developing fetus?
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The uterus protects and nourishes the fetus
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