Answer:
t = -1.428
Step-by-step explanation:
Average blood pressure among people with high responsibility jobs = u = 140 mm
Number of people sampled for the study = n = 51
Average blood pressure of the sample = x = 139 mm
Standard deviation of the sample = s = 5 mm
The claim is that practicing yoga decreases the blood pressure. So we have to test that after practicing yoga, the average blood pressure will be lesser than 140. Based on this we can formulate the null and alternate hypothesis as:
Null Hypothesis: 
Alternate Hypothesis: 
Since population standard deviation is not known, we cannot use z-distribution for this test. We are given the value of sample standard deviation, so t-test will be used for this case.
Test statistic is calculated as:

Using the values in this formula gives us:

Therefore, the value of test statistic is -1.428
Answer:
See photo below
Add arrows to the two ends of the parabola.
Step-by-step explanation:
To sketch this quadratic function, we to connect three dots: the two roots and a vertex.
The given roots are -1 and 1.
Draw <u>two dots at the x-intercepts</u>, which are (-1, 0) and (1, 0).
Vertex dot: V (x, y)
The vertex x-coordinate always in the middle of the two roots. The middle of -1 and 1 is 0. That's the same as the y-axis.
V (0, y)
Since the function increases when x < 0, the parabola will <u>open up</u>.
We read from left to right. The greater numbers are towards the top of the page.
<u>You can put the vertex anywhere on the y-axis that is below the x-axis.</u>
A
explanation:
2x+10=-6-30
8x+40=0
x=-5