Answer:
The surface area is equal to 
Step-by-step explanation:
The surface area of the triangular pyramid is equal to the area of its four triangular faces
so
In this problem
![SA=4[\frac{1}{2}(b)(h)]](https://tex.z-dn.net/?f=SA%3D4%5B%5Cfrac%7B1%7D%7B2%7D%28b%29%28h%29%5D)
we have
substitute the values
![SA=4[\frac{1}{2}(15)(13)]=390\ in^{2}](https://tex.z-dn.net/?f=SA%3D4%5B%5Cfrac%7B1%7D%7B2%7D%2815%29%2813%29%5D%3D390%5C%20in%5E%7B2%7D)
OptionAStep-by-step explanation:95% confidence interval is obtained using the following formulaCOnfidence interval lower bound = mean - critical value * sigma/sq rt nand upper bound = mean + critical value*sigma/sq rt nThus margin of error = critical value*sigma/rt nvaries indirectly as n provided others are remaining the same.Hence lower sample indicates higher margin of errorOut of 4 options given we find that 1 option has maximum margin of error as 21%Hence option. A is most likely coming from a small sample.
The best way to remember which place is rounded to the nearest 10th, 100th, 1000th, etc., is by counting the number of 0's.
This question wants you to round to the nearest 10th.
How many 0's does 10 have? 1.
So we round one space after the decimal.
This gets us 73.2
