Answer: A) The 'lub' sound is caused as the atrioventricular valves close.
Explanation:
USATestprep just answered it
A hypothesis for this observation might be that malaria is not endemic to southern Africa. It is a plausible explanation of a given scientific question.
<h3>Hypothesis and scientific method</h3>
A hypothesis is a plausible explanation of an observation of the natural world, which must be tested by using the scientific method.
Testing a hypothesis involves performing additional observational and/or experimental procedures in order to confirm or reject this assumption.
In this case, the sickle cell allele is found in high frequency in regions where malaria is endemic.
Learn more about hypotheses here:
brainly.com/question/11555274
Yes, rennin<span>. [ren´in].: the milk-curdling enzyme found in the gastric juice of human infants ... was formerly used extensively as a </span>curdling agent<span> by the cheese industry.</span>
I’m pretty sure The answer Is D. I did the test not to long ago and I got it all right. :)
