Answer:
<em><u>A. Neither the subjects nor the researchers can bias the results.</u></em>
Explanation:
As described, a double- blind study is one in which the researcher and his study does not know the person receiving the actual treatment.
Researchers can be bias in their studies as they seek to establish and fine tune results in the way the best favors them. A double-blind study helps to bridge this gap to prevent bias that might be introduced into an experimental set up or while interpreting results.
Answer:
900 nanometer (nm)
Explanation:
Given that,
Length of a bacterial cell = 0.9 micrometer (µm)
There is a direct relationship between the nanometer and the micrometer scale,
It is that 1 micrometer (μm) = 1000 nanometer (nm)
Therefore, 0.9 μm = 900 nm
Thus, the length of the given bacterial cell is 900 nanometer (nm).
Answer
Characteristics of young rivers are;
• The river is small and flows with less energy down steep slopes
• Features formed are a result of erosion
• These rivers form V-shaped valley
• Form interlocking spurs when they meet obstacles
Explanation
A river in its youthful stages has a steep river gradient. The river is in most cases narrow and deep. Waterfalls and rapids are common in youthful stages of a river. The river channel is considered narrow and deep, with a V-shaped valley present. Vertical erosion is dominant and the channel of the river generally winds.
The scale used is the Richter scale.
Hope it helped!
