Answer: is D
Step-by-step explanation:
Answer:
b. 2.333
Step-by-step explanation:
Test if the mean transaction time exceeds 60 seconds.
At the null hypothesis, we test if the mean transaction time is of 60 seconds, that is:

At the alternate hypothesis, we test if it exceeds, that is:

The test statistic is:

In which X is the sample mean,
is the value tested at the null hypothesis, s is the standard deviation of the sample and n is the size of the sample.
60 is tested at the null hypothesis:
This means that 
A sample of 16 ATM transactions shows a mean transaction time of 67 seconds with a standard deviation of 12 seconds.
This means that 
Value of the test statistic:




Thus, the correct answer is given by option b.
Check the picture below.
let's notice that the base of the pyramid is triangle with a base of 5 and an altitude of 4, so it has an area of (1/2)(5)(4).
![\bf \textit{volume of a pyramid}\\\\ V=\cfrac{1}{3}Bh~~ \begin{cases} B=\stackrel{\textit{area of its}}{base}\\ h=height\\[-0.5em] \hrulefill\\ B=\frac{1}{2}(5)(4)\\ h=8 \end{cases}\implies V=\cfrac{1}{3}\left( \cfrac{1}{2}(5)(4) \right)(8)\implies V=\cfrac{1}{3}(10)(8) \\\\\\ V=\cfrac{80}{3}\implies V=26\frac{2}{3}](https://tex.z-dn.net/?f=%5Cbf%20%5Ctextit%7Bvolume%20of%20a%20pyramid%7D%5C%5C%5C%5C%20V%3D%5Ccfrac%7B1%7D%7B3%7DBh~~%20%5Cbegin%7Bcases%7D%20B%3D%5Cstackrel%7B%5Ctextit%7Barea%20of%20its%7D%7D%7Bbase%7D%5C%5C%20h%3Dheight%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20B%3D%5Cfrac%7B1%7D%7B2%7D%285%29%284%29%5C%5C%20h%3D8%20%5Cend%7Bcases%7D%5Cimplies%20V%3D%5Ccfrac%7B1%7D%7B3%7D%5Cleft%28%20%5Ccfrac%7B1%7D%7B2%7D%285%29%284%29%20%5Cright%29%288%29%5Cimplies%20V%3D%5Ccfrac%7B1%7D%7B3%7D%2810%29%288%29%20%5C%5C%5C%5C%5C%5C%20V%3D%5Ccfrac%7B80%7D%7B3%7D%5Cimplies%20V%3D26%5Cfrac%7B2%7D%7B3%7D)