<span>is operated by the U.S. Coast Guard</span>
The correct answer is A. Nebula, star of seven stellar masses, a red supergiant, supernova, black hole.
Explanation
Stars have a life cycle that begins with the gravitational collapse of a gaseous nebula. Subsequently, thermonuclear fusion occurs that allows the conversion of hydrogen into helium, this causes the released energy to pass through the star and radiate in a phase called the star of seven stellar masses. After several billion years, the star passes to the "red giant" stage. Here the star contracts and raises its temperature. After this, the stars (which have masses greater than the sun) detach from their layers forming supernovae, and later, these give rise to "black holes". According to the above, the correct answer is A. Nebula, star of seven stellar masses, a red supergiant, supernova, black hole.
Answer: The relationship between blood pressure and heart rate responses to coughing was investigated in 10 healthy subjects in three body positions and compared with the circulatory responses to commonly used autonomic function tests: forced breathing, standing up and the Valsalva manoeuvre. 2. We observed a concomitant intra-cough increase in supine heart rate and blood pressure and a sustained post-cough elevation of heart rate in the absence of arterial hypotension. These findings indicate that the sustained increase in heart rate in response to coughing is not caused by arterial hypotension and that these heart rate changes are not under arterial baroreflex control. 3. The maximal change in heart rate in response to coughing (28 +/- 8 beats/min) was comparable with the response to forced breathing (29 +/- 9 beats/min, P greater than 0.4), with a reasonable correlation (r = 0.67, P less than 0.05), and smaller than the change in response to standing up (41 +/- 9 beats/min, P less than 0.01) and to the Valsalva manoeuvre (39 +/- 13 beats/min, P less than 0.01). 4. Quantifying the initial heart rate response to coughing offers no advantage in measuring cardiac acceleratory capacity; standing up and the Valsalva manoeuvre are superior to coughing in evaluating arterial baroreflex cardiovascular function.
Explanation:
Imagine you are surveying a population of a mountain range where the inhabitants live in the valleys with no inhabitants on the large mountains between. If your sample area is the valleys, and you use this to estimate the population across the entire mountain range, <u>you overestimate the actual population size</u>
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Explanation:
- An estimate that turns out to be incorrect will be an overestimate if the estimate exceeded the actual result, and an underestimate if the estimate fell short of the actual result.
- The mean of the sampling distribution of a statistic is sometimes referred to as the expected value of the statistic. Therefore the sample mean is an unbiased estimate of μ.
- Any given sample mean may underestimate or overestimate μ, but there is no systematic tendency for sample means to either under or overestimate μ.
- Bias is the tendency of a statistic to overestimate or underestimate a parameter. Bias can seep into your results for a slew of reasons including sampling or measurement errors, or unrepresentative samples
