Answer:
Correct option: B. 90%
Explanation:
The confidence interval is given by:
![CI = [\bar{x} - z\sigma_{\bar{x}} , \bar{x}+z\sigma_{\bar{x}} ]](https://tex.z-dn.net/?f=CI%20%3D%20%5B%5Cbar%7Bx%7D%20-%20z%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%2C%20%5Cbar%7Bx%7D%2Bz%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%5D)
If 
is 190, we can find the value of 
:
Now we need to find the value of 
:
So the value of z is 1.71.
Looking at the z-table, the z value that gives a z-score of 1.71 is 0.0436
This value will occur in both sides of the normal curve, so the confidence level is:
The nearest CI in the options is 90%, so the correct option is B.
Answer: 24 pA
Explanation:
As pure silicon is a semiconductor, the resistivity value is strongly dependent of temperature, as the main responsible for conductivity, the number of charge carriers (both electrons and holes) does.
Based on these considerations, we found that at room temperature, pure silicon resistivity can be approximated as 2.1. 10⁵ Ω cm.
The resistance R of a given resistor, is expressed by the following formula:
R = ρ L / A
Replacing by the values for resistivity, L and A, we have
R = 2.1. 10⁵ Ω cm. (10⁴ μm/cm). 50 μm/ 0.5 μm2
R = 2.1. 10¹¹ Ω
Assuming that we can apply Ohm´s Law, the current that would pass through this resistor for an applied voltage of 5 V, is as follows:
I = V/R = 5 V / 2.1.10¹¹ Ω = 2.38. 10⁻¹¹ A= 24 pA
The workers went to bed hungry probably because they are hard workers and so didn’t want to eat because they didn’t want to take break┌(;￣◇￣)┘
Answer: Option D is not true of hydraulic valves. A hydraulic valve is a device that can change the opening degree of liquid flow path
Explanation:
The pilot check valve allows flow of liquid in one direction and blocks flow in the opposite direction
