Answer:
(a) 2 degree celsius per hour
(b) 3 degree celsius per hour.
Step-by-step explanation:
From the question,
(a) Avearge rate of rise in temperature per hour(T') = Rise in temperature(T)/Time required for the rise(t).
T' = T/t.................... Euqation 1
Rise in temperature (T) = 4 degree celsius, t = 10.00 am to noon = 2 hours.
Substitute into equation 1
T' = 4/2
T' = 2 degree celsius per hour.
(b) Also,
Average rate of fall in temperature per hour (T') = Fall in temperature (T)/Time(t)
T' = T/t
Given: T = 6 degree celsius, t = 3:00 pm to 5:00 pm = 2 hours
T' = 6/2
T' = 3 degree celsius per hour
This question not incomplete
Complete Question
The life of a semiconductor laser at a constant power is normally distributed with a mean of 7,000 hours and a standard deviation of 600 hours. If three lasers are used in a product and they are assumed to fail independently, the probability that all three are still operating after 7,000 hours is closest to? Assuming percentile = 95%
Answer:
0.125
Step-by-step explanation:
Assuming for 95%
z score for 95th percentile = 1.645
We find the Probability using z table.
P(z = 1.645) = P( x ≤ 7000)
= P(x<Z) = 0.95
After 7000 hours = P > 7000
= 1 - P(x < 7000)
= 1 - 0.95
= 0.05
If three lasers are used in a product and they are assumed to fail independently, the probability that all three are still operating after 7,000 hours is calculated as:
(P > 7000)³
(0.05)³ = 0.125
The rock's height is increasing in the interval from 0 seconds to 3 seconds.
At time 0 the rock starts moving upward from 52 foot until it reachs 180 foot height (time 3 seconds). Then the rock starts to descend, which means that the height starts to decrease.
Step-by-step explanation:
5(2h+8) <60
10h +40< 60
10h + 40-40 < 60-40
10h < 20
10h/10 < 20/10
h < 2