Answer:
At a speed of 57 mph for 8 hr a driver will travel 456 mi
Step-by-step explanation:
Here we have a summary of the letters for each variable:
Speed ---> r (in units of mph)
Time ---> t (in units of hr)
Distance ---> d (in units of mi)
These three variables are related by the next formula:
d = rt
In the data they give to you: 57 mph and 8 hr, they are telling you the r and the t, respectively:
r = 57 mph
t = 8 hr
The only thing you have to do is replace the values:
d = rt ----> d = 57 mph x 8 hr
d = 456 mi
Firstly, we'll fix the postions where the 
women will be. We have 
forms to do that. So, we'll obtain a row like:
The n+1 spaces represented by the underline positions will receive the men of the row. Then,
Since there is no women sitting together, we must write that 
. It guarantees that there is at least one man between two consecutive women. We'll do some substitutions:
The equation (i) can be rewritten as:
We obtained a linear problem of non-negative integer solutions in (ii). The number of solutions to this type of problem are known: ![\dfrac{[(n)+(m-n+1)]!}{(n)!(m-n+1)!}=\dfrac{(m+1)!}{n!(m-n+1)!}](https://tex.z-dn.net/?f=%5Cdfrac%7B%5B%28n%29%2B%28m-n%2B1%29%5D%21%7D%7B%28n%29%21%28m-n%2B1%29%21%7D%3D%5Cdfrac%7B%28m%2B1%29%21%7D%7Bn%21%28m-n%2B1%29%21%7D)
[I can write the proof if you want]
Now, we just have to calculate the number of forms to permute the men that are dispposed in the row: 
Multiplying all results:
Answer:
Mmm either B or D one of those two
