Answer:
The fourth graph (last graph)
Step-by-step explanation:
Remember that the zeros of a function are the x-intercepts of the graph. To find the zeros we just need to set the function equal to zero and solve for x:




Now we know that the graph or our function intersects the x-axis at x = 1 and x = -4.
Since both x values inside the parenthesis are positive, our parabola is opening upwards.
The only graph opening upwards whose x-intercepts are x = 1 and x = -4 is the fourth one.
We can conclude that the graph of
is the fourth one.
169 if you take 13 times 3 you get 39. And 10 times 13 is 130. Add those together and you gat 169
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.
11,513 is the answer I really don't know how to write it all out sorry