Answer:
1,919.1
Step-by-step explanation:
I know that's the answer
Answer: The mean number of checks written per day 
Standard deviation
Variance 
Step-by-step explanation:
Given : The total number of checks wrote by person in a year = 126
Assume that the year is not a leap year.
Then 1 year = 365 days
Let the random variable x represent the number of checks he wrote in one day.
Then , the mean number of checks wrote by person each days id=s given by :-

Since , the distribution is Poisson distribution , then the variance must equal to the mean value i.e. 
Standard deviation : 
Answer:
At 43.2°.
Step-by-step explanation:
To find the angle we need to use the following equation:

Where:
d: is the separation of the grating
m: is the order of the maximum
λ: is the wavelength
θ: is the angle
At the first-order maximum (m=1) at 20.0 degrees we have:

Now, to produce a second-order maximum (m=2) the angle must be:


Therefore, the diffraction grating will produce a second-order maximum for the light at 43.2°.
I hope it helps you!
Answer:
S = a² => 20 = a² => a = √20 ≈ 4.5 cm
Step-by-step explanation:
Answer: His mom's age is 48
Step-by-step explanation: If his age is 1/4 his mother, then if we know his age, we do the opposite. Multiply his age by 4, we get 48.