Answer:
its b
Step-by-step explanation:
The distance between their house and the school from the information given will be 777.60 meters.
<h3>How to calculate the distance?</h3>
The distance between their house and the school will be:
= 80 × 81 × 12
= 77760cm
= 777.60 meters.
When Diane takes 16 min to walk to school, the length of her steps will be:
= 77760/(16 × 90)
= 54 cm
Learn more about distance on:
brainly.com/question/17273444
If it's compounded annually, it basically means the interest rate will apply once a year.
So the answer will be 1.
Answer:
There is a 99.99998% probability that at least one valve opens.
Step-by-step explanation:
For each valve there are only two possible outcomes. Either it opens on demand, or it does not. This means that we use the binomial probability distribution to solve this problem.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinatios of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
In this problem we have that:

Calculate P(at least one valve opens).
This is 
Either no valves open, or at least one does. The sum of the probabilities of these events is decimal 1. So:


So


Finally

There is a 99.99998% probability that at least one valve opens.
To find the average, add the cost of each book to get a total cost, then divide the total cost by the number of books purchased.
Total cost: 32 + 45 + 39 = 116
Average cost: 116 / 3 = 38.67