Answer:
Explanation:
a. Cast iron or Aluminium alloy are typically used. Aluminium is much lighter in weight and it can transfer heat better to the coolant. While Cast Iron is typically stronger and is thus still used by the manufacturers.
b. Copper can be used as a condensing heat exchanger for hot steam due to its optimal thermal properties and its ability to resist corrosion.
c. high-speed steel are perfect for producing drill bits because of its hardness and resistance to heat to an extent. Drill bits tend to produce heat as a result of the friction between it and the material to be drilled.
d. lead can be used as a container for strong acids because of its anti-corrosive properties
e.zinc and copper can be used as fuel in pyrotechnics mainly due to the fact that burn with refreshing colours. Aluminium can also be used.
f. Platinum is the metal that best suits this purpose because of its high melting point and resistivity to oxidation.
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:
2750
Explanation:
The number of windings and the voltage are proportional.
__
Let n represent the number of windings to produce 110 Vac. Then the proportion is ...
n/110 = 300,000/12,000
n = 110(300/12) = 2750 . . . . multiply by 110
2750 windings would be needed to produce 110 Vac at the output.
Answer:
C = 292 Mbps
Explanation:
Given:
- Signal Transmitted Power P = 250mW
- The noise in channel N = 10 uW
- The signal bandwidth W = 20 MHz
Find:
what is the maximum capacity of the channel?
Solution:
-The capacity of the channel is given by Shannon's Formula:
C = W*log_2 ( 1 + P/N)
- Plug the values in:
C = (20*10^6)*log_2 ( 1 + 250*10^-3/10)
C = (20*10^6)*log_2 (25001)
C = (20*10^6)*14.6096
C = 292 Mbps
Answer: environmental impact
Explanation:
From the question, we are informed that Harlin is designing a new car engine that does not create pollution.
The technological design factor which is probably the most important for the design is the impact on the environment.
Pollution has a negative effect on the environment a d doing this shows that emphasis is placed on how the environmental issue of pollution can be tackled.