Answer:
the answer is number three
2.8 or if rounded to the nearest tenth so 2.8√8
Answer:
-11 and lower
Step-by-step explanation:
it's saying that -10 is as low as the number can possibly be or equal to it.
There are 651.335 million cells in the petri dish after 11 hours and the cells will reach 1 billion cells after 14.068 hours
<h3>How to determine the number of cells after 11 hours?</h3>
The given parameters are:
At t = 0, Bacteria = 140 million
At t = 6, Bacteria = 320 million
This can be represented as:
f(0) = 140
f(6) = 320
An exponential function is represented as:
f(t) = f(0) * r^t
When t = 6, we have:
320 = 140 * r^6
Divide both sides by 140
r^6 = 2.28571428571
Take the 6th root of both sides
r = 1.15
So, we have:
f(t) = f(0) * 1.15^t
Substitute f(0) = 140
f(t) = 140 * 1.15^t
After 11 hours, we have:
f(11) = 140 * 1.15^11
Evaluate
f(11) = 651.33
Hence, there are 651.335 million cells in the petri dish after 11 hours
Time to reach 1 billion cells
This means that
f(t) = 1 billion i.e. 1000 million
So, we have:
1000 = 140 * 1.15^t
Divide by 140
1.15^t = 7.14285714286
Take the logarithm of both sides
t * log(1.15) = log(7.14285714286)
Divide both sides by log(1.15)
t = 14.068
Hence, the cells will reach 1 billion cells after 14.068 hours
Read more about exponential functions at:
brainly.com/question/2456547
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Answer:
The null and alternative hypotheses are:


Under the null hypothesis, the test statistic is:

Where:
is the sample mean
is the sample standard deviation
is the sample size

Now, the right tailed t critical value at 0.05 significance level for df = n-1 = 10-1 = 9 is:

Since the t statistic is less than the t critical value at 0.05 significance level, therefore,we fail to reject the null hypothesis and conclude that there is not sufficient evidence to support the claim that the average phone bill has increased.