Answer: 
Step-by-step explanation:
To polygons are said to be similar if all the corresponding angles of given polygons are equal.
In the given figure, it can be seen that in quadrilateral FSHB and quadrilateral KTWJ all the corresponding angles are equal.
∠F=∠K
∠S=∠T
∠H=∠W
∠B=∠J
Therefore, The given polygons are similar.
Hence, 
The answer is 40cm = 2000km
The unit rate is 50km per cm, so 40cm is 40*50 km
40*50= 2000km
The correct answer is Choice A.
This is an example of an exponential equation, so we need the formula

.
The a value is the starting value of 100. The b value must be a decimal lower than 1 because it is decreases.
If you substitute in 8 for x, you will see that the output is about 50 (half of 100).
Didn't know if this was a question but if yes it is