We need to define the variables,
So,

Therefore, the probability that the repair time is more than 4 horus can be calculate as,

The probability that the repair time is more than 4 hours is 0.136
b) The probability that repair time is at least 12 hours given that the repair time is more than 7 hoirs is calculated as,


The probability that repair time is at least 12 hours given that the repair time is more than 7 hours is 0.63
Answer: they are connected in series.
Explanation:
Answer:
The hardenability increases with increasing austenite grain size, because the grain boundary area is decreasing. This means that the sites for the nucleation of ferrite and pearlite are being reduced in number, with the result that these transformations are slowed down, and the hardenability is therefore increased.
The equivalent of the resistance connected in the series will be Req=R₁+R₂+R₃.
<h3>
What is resistance?</h3>
Resistance is the obstruction offered whenever the current is flowing through the circuit.
So the equivalent resistance is when three resistances are connected in series. When the resistances are connected in series then the voltage is different and the current remain same in each resistance.
V eq = V₁ + V₂ + V₃
IReq = IR₁ + IR₂ + IR₃
Req = R₁ + R₂ + R₃
Therefore the equivalent of the resistance connected in the series will be Req=R₁+R₂+R₃.
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