Answer:
D.the product is negative
for example
2×-1
=-2
Answer: D
H0: μ=522
H1: μ>522
Step-by-step explanation:
The null hypothesis (H0) tries to show that no significant variation exists between variables or that a single variable is no different than its mean. While an alternative Hypothesis (Ha) attempt to prove that a new theory is true rather than the old one. That a variable is significantly different from the mean.
So, for this case;
The null hypothesis is that the mean score equals to 522
H0: μ=522
The alternative hypothesis is that the mean score is greater than 522.
H1: μ>522
Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
That is z with a pvalue of 
, so Z = 1.28.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
parallel means "same slope (m)"
m = 
= 
Now, input the point (0, 0) and the slope 
into the Point-Slope formula:
y - y₁ = m(x - x₁)
y - 0 = 
(x - 0)
y = 
3y = -5x <em>multiplied both sides by 3</em>
0 = -5x - 3y <em>subtracted 3y from both sides</em>
Answer: C
4b. Laura has a 12-foot ladder. The safety instructions recommend the
base of the ladder be placed 4 feet from the base of the wall. How highwill the ladder be able to reach on the wall? WRITE YOUR ANSWER AS A SIMPLIFIED RADICAL. (HINT: Use the abbreviation sqrt to mean "square root of." For example an answer might look like 5sqrt3, and be read "five times the square root of 3".)
