Answer:
a.divide 100 by 1.609
Explanation:
We know the relation between miles and kilometers
1 mile = 1.609 km
Now, we have to convert 100 km to miles.
Let x miles in 100 kilometers.
Hence, we have

Therefore, we can see that we have divided 100 by 1.609 in order to find the number of miles in 100 km.
Therefore, a is the correct option.