Given: "<span>B(t)=4*e^0.8t, How many hours will it take for the population to grow to 400?" Set B(t) = 400. Then:
400=4*e^(0.8t), or
100 = e^(0.8t)
Take the natural log of both sides, obtaining
ln 100
ln 100 = 0.8t. Then t = ----------- = 5.76 hours.
0.8</span>
Answer:
Step-by-step explanation:
Dentist's Office = 5/6 of an hour. An hours is 60 minutes
therefore he spent 5/6 x 60 = 50 minutes at the Dentist
1/10 of those 50 minutes were spent in the waiting room that is 1/10 x 50 = 5 minutes
Therefore Sam Spent 45 minutes at the Dentist office
I think the second part of your question is missing
Using the normal distribution, it is found that the life span of an appliance that has a z-score of –3 is of 24 months.
<h3>Normal Probability Distribution</h3>
The z-score of a measure X of a normally distributed variable with mean
and standard deviation
is given by:

- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
In this problem, the parameters are given as follows:
.
Hence:


X - 48 = -24
X = 24.
The life span of an appliance that has a z-score of –3 is of 24 months.
More can be learned about the normal distribution at brainly.com/question/24663213
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Answer:
5
Step-by-step explanation: