Answer:
Step-by-step explanation:
Hello!
To study the threshold of hering the researcher took a random sample of 80 male college freshmen.
The students underwent an audiometry test where a tome was played and they had to press a button when they detected it. The researcher recorded the lowest stimulus level at which the tone was detected obtaining a sample mean of X[bar]= 22.2 dB and a standard deviation of S= 2.1 dB
To estimate the population mean, since we don't have information about the variable distribution but the sample size is greater than 30, you can use the approximation of the standard normal distribution:
X[bar] ± 
Where the semiamplitude or margin of error of the interval is:
d=
Using a 95% level 
d= 1.965 * 
d= 0.46
The point estimate of the population mean of the threshold of hearing for male college freshmen is X[bar]= 22.2 db
And the estimation using a 95%CI is [21.74;22.66]
I hope this helps!
There two zero’s hopefully
Volume of a cylinder = π r² h
Let us assume the following values:
radius = 9
height = 10
Volume = 3.14 * 9² * 10
= 3.14 * 81 *10
Volume = 2,543.40
Changes:
radius is reduced to 2/9 of its original size = 9 x 2/9 = 2
height is quadrupled = 10 x 4 = 40
Volume = π r² h
= 3.14 * 2² * 40
= 3.14 * 4 * 40
Volume = 502.40
Original volume = 2543.40 V.S. Volume after change = 502.40
The volume of an oblique cylinder decreased when its radius was decreased to 2/9 of its original size and its height is increased 4 times.
Question #2
Erica will have to work for 14 hours in order to buy her sneakers.
How to solve:
You subtract $31 from $150 which equals to $119
You multiply 8.50 (which is the amount of money she gets paid every hour) by the answers they gave you.
8.50 multiplied by 14 is 199
Erica had to work 14 hours to make $199
Your answer is D) 14
Because force= acceleration x mass Acceleration is constant for a body of any mass since force is exactly proportional to mass.
