Answer: 1.960
Step-by-step explanation:
The value of z we use to calculate a confidence interval with a (
) confidence level is a two-tailed test value i.e. represented by :-

Given : The level of confidence: 
Then, significance level : 
With the help of standard normal distribution table for z , we have

Hence, the value of z should be used to calculate a confidence interval with a 95% confidence level =1.960
Answer:
y= -x+7, b= sqrt(2P/a), c=3P^2-b
Step-by-step explanation:
First, make a table regarding both of the equations. You will eventually find out that both lines intersect at the point (2, 5) after you find the points on the table. From there, subtract x from both sides in the equation x + y = 2. You will get y = -x + 2. Since they said the line was parallel, find a line that has the slope of negative one. Since we know that this line intersects the point in which the first two lines intersect, we know that the y-intercept will be 7. The equation of the line would be y=-x+7.
Multiply both sides by 2. Then, divide both sides by a to get b^2=(2P/a). Take the square root to get the value of b, which is sqrt(2P/a).
Square both sides of the equation to get P^2=(b+c)/3. Cross multiply to get 3P^2=b+c. Subtract b from both sides to get c=3P^2-b.
This can be written as:

"No greater than" does not necessarily mean less than, but it just means it cannot go over. So equal to or less than.
"The difference of a number and 2" can be represented as "n - 2"
If you were to solve this inequality, you would end up getting:

or

Hope this helps! :)
David will finish first, because if you divide Brad's miles by 2 to his miles in a 1/4 of an hour are 5.95 miles. This means David went 6.2 miles in the same time that Brad went 5.95. Therefore, David will finish first.