Answer:
Part (A): The correct option is true.
Part (B): The null and alternative hypothesis should be:
Step-by-step explanation:
Consider the provided information.
Part (A)
A random sample of 100 students from a large university.
Increasing the sample size decreases the confidence intervals, as it increases the standard error.
If the researcher increase the sample size to 150 which is greater than 100 that will decrease the confidence intervals or the researcher could produce a narrower confidence interval.
Hence, the correct option is true.
Part (B)
The researcher wants to identify that whether there is any significant difference between the measurement of the blood pressure.
Therefore, the null and alternative hypothesis should be:
a) 62.855m
We will need to use the Pythagorean Theorem here, as we know a and c, but not b. I have attached an image of a triangle sketch to set up the problem, which should hopefully help us to visualize this problem a bit better.
Pythagorean Theorem: a^2 + b^2 = c^2
(19.8)^2 + b^2 = (65.9)^2
392.04 + b^2 = 4342.81
b^2 = 3950.77
b = 62.855 (rounded to 3 places)
b) m = 0.315
The gradient is also known as the slope. I've shown what the points would be in the image attached. Now that we know the value of b (x in the points in image), we can use points E and C to find the slope.
Point 1: (0,0)
Point 2: (62.855, 19.8)
m = (19.8 - 0) / (62.855 - 0)
m = 19.8 / 62.855
m = 0.315 (rounded to three places)
c) 17.485 degrees
The angle of inclination would be angle C. To find angle C, we will need to use an inverse trigonometry function. Any can be used since we know all of the side lengths, but I will show Sine here, opposite / hypotenuse.
sin(x) = 19.8 / 65.9
x = sin^-1 (19.8/65.9)
x = 17.485 degrees (rounded to 3 places)
Hope this helps!! :)
Answer: 2500 years
Step-by-step explanation:
I'm not quite sure if I'm doing this right myself but I'll give it a shot.
We use this formula to find half-life but we can just plug in the numbers we know to find <em>t</em>.
We know half-life is 5730 years and that the parchment has retained 74% of its Carbon-14. For 
let's just assume that there are 100 original atoms of Carbon-14 and for A(t) let's assume there are 74 Carbon-14 atoms AFTER the amount of time has passed. That way, 74% of the C-14 still remains as 74/100 is 74%. Not quite sure how to explain it but I hope you get it. <em>h</em> is the last variable we need to know and it's just the half-life, which has been given to us already, 5730 years, so now we have this.
Now, solve. First, divide by 100.
Take the log of everything
Divide the entire equation by log (0.5) and multiply the entire equation by 5730 to isolate the <em>t</em> and get
Use your calculator to solve that giant mess for <em>t </em>and you'll get that <em>t</em> is roughly 2489.128182 years. Round that to the nearest hundred years, and you'll find the hopefully correct answer is 2500 years.
Really hope that all the equations that I wrote came out good and that that's right, this is definitely the longest answer I've ever written.
2,000,000 because 24/12 is 2 so you double it twice
Answer:
see explanation
Step-by-step explanation:
The diagrams show triangular figures
The first figure has 1 dot
The second has 1 + 2 = 3 dots
The third has 3 + 3 = 6 dots
The fourth has 6 + 4 = 10 dots
Note the pattern is + 2 , + 3, + 4
Thus the fifth pattern is 10 + 5 = 15 dots
