Answer: You are correct. The mode is between 90 and 100
This is because the tallest bar corresponds to this interval. The mode is the most frequent value.
Answer:
The minimum percentage of noise level readings within 8 standard deviations of the mean is 98.44%.
Step-by-step explanation:
When we do not know the shape of the distribution, we use the Chebyshev's Theorem to find the minimum percentage of a measure within k standard deviations of the mean.
This percentage is:

Within 8 standard deviations of the mean
This means that
. So

The minimum percentage of noise level readings within 8 standard deviations of the mean is 98.44%.
Red blood cell, as they have a biconcave shape and need to store a lot of haemoglobin, the pigment of blood
hope this helps! :)