Answer:“If we’ve covered all of the potential sources, and we know the unique signature of the sand from these different sources, and we find it on a beach somewhere, then we basically know where it came from,” explained Barnard.
Explanation:
I think it's A but it might be different from your school and mine
Answer:
Ea=5.5 Kcal/mole
Explanation:
Let rate constant are 
and 
at temperature 
and 
By using Arrhenius equation at two different two different temperature,
By putting value of R=2 cal/mole.K
By rounding off upto 2 significant figure;
Answer:
At this partial pressure of oxygen, Mb would be almost completely saturated but Hb would not.
Explanation:
The oxygen saturation curves for Mb and Hb are quite different. The curve for Mb is hyperbolic while that for Hb is sigmoidal.
Mb reaches oxygen saturation before Hb.
Thus, at a partial pressure of 40 mmHg, Mb is almost completely saturated but Hb is not.
A change which would remove the source of this error is to: Test a fourth group, in which participants do not receive the mineral supplements.
<h3>What is a scientific method?</h3>
A scientific method can be defined as the various techniques that are adopted to observe, investigate, examine and study a particular thing while giving explanations on the basis of the evidence, theory, proof, hypothesis, or factual information they derived from the research work.
In this scenario, a claim was made by the company its mineral supplements can effectively prevent common cold. However, this claim was disputed by a scientist because there exist an error in the group setup.
<h3>How to remove an error in science</h3>
For this investigation, an effective and efficient way to remove this source of error would be by testing a fourth group, in which the mineral supplements is not administered to any of the participants.
Read more on scientific method here: brainly.com/question/17216882
