I added a screenshot with the complete question
<u><em>Answer:</em></u>Total miles = 2.5 miles
<u><em>Explanation:</em></u><u>1- While walking:</u>
We are given that Joelle walked 20 minutes at a rate of 3 miles per hour.
This means that she walked

of an hour at a rate of 3 miles per hour
The formula that relates distance, time and velocity is:
Distance = velocity * time<u>Substitute with the givens to get the distance she covered while walking:</u>
Distance = 3 *

= 1 mile
<u>2- While running:</u>
We are given that Joelle ran 15 minutes at a rate of 6 miles per hour
This means that she ran

of an hour at a rate of 6 miles per hour
The formula that relates distance, time and velocity is:
Distance = velocity * time<u>Substitute with the givens to get the distance she covered while running:</u>
Distance = 6 *

= 1.5 miles
<u>3- getting the total mileage:</u>
Total distance she covered = distance while walking + distance while running
Total distance she covered = 1 + 1.5
Total distance she covered = 2.5 miles
Hope this helps :)
Answer: A
If he has 15$ then he could spend all of it on the colored pencils, so there has to be a black dot on 15, & if he could buy the colored pencils less than 15$ then it has to be a black dot on 15 & an arrow pointing to less than 15
I hope this answers your question
The expected length of code for one encoded symbol is

where
is the probability of picking the letter
, and
is the length of code needed to encode
.
is given to us, and we have

so that we expect a contribution of

bits to the code per encoded letter. For a string of length
, we would then expect
.
By definition of variance, we have
![\mathrm{Var}[L]=E\left[(L-E[L])^2\right]=E[L^2]-E[L]^2](https://tex.z-dn.net/?f=%5Cmathrm%7BVar%7D%5BL%5D%3DE%5Cleft%5B%28L-E%5BL%5D%29%5E2%5Cright%5D%3DE%5BL%5E2%5D-E%5BL%5D%5E2)
For a string consisting of one letter, we have

so that the variance for the length such a string is

"squared" bits per encoded letter. For a string of length
, we would get
.
392,200 because the 5 makes the 1 round up to 2 so it’s 392,200