Answer:
The sample size is 
Step-by-step explanation:
From the question we are told that
The margin of error is E = 1.5 seconds
The standard deviation is s = 4 seconds
Given that the confidence level is 97% then the level of significance is mathematically represented as
=> 
Generally from the normal distribution table the critical value of 
is
Generally the sample size is mathematically represented as
![n =[ \frac{Z_{\frac{\sigma }{2 } } * \sigma }{E} ]^2](https://tex.z-dn.net/?f=n%20%20%3D%5B%20%20%5Cfrac%7BZ_%7B%5Cfrac%7B%5Csigma%20%7D%7B2%20%7D%20%7D%20%2A%20%20%5Csigma%20%7D%7BE%7D%20%5D%5E2)
=> ![n =[ \frac{2.17 * 4 }{1.5} ]^2](https://tex.z-dn.net/?f=n%20%20%3D%5B%20%20%5Cfrac%7B2.17%20%20%2A%204%20%7D%7B1.5%7D%20%5D%5E2)
=>
72.9°
use tangent.
from the corner y look for the opposite and adjacent sides to your angle.
the opposite side from corner y is 13
the adjacent side from the corner is 4
tanY = 13/4
Y = inverse tangent of 13/4
72.897
Atomic Mass on the Elements
Ok so the first step is to -1 from both sides. On the right side it cancels out and on the left side it = -16. So now your left with -16= 8x. Your still not done yet though. So now what you want to do is divide both sides by 8. On the right side it cancels out and you bring down x and on the left side it equals -2. So x=-2. So to verify it you have to plu -2 back into the equation. So -15= 8 Times -2 +1 so 8 Times -2 = -16 plus one is -15. Hoped that helped!!
