Answer:
Option 3 is correct that is 
Step-by-step explanation:
We have general formula for sum of cube which is

Here, we have a=s and b=6
on substituting the values in the formula we will get

After simplification we will get

After rearranging the terms we will get
which exactly matches option 3 in the given options.
Therefore, option 3 is correct that is 
Each friend spent $50 (50+50+50= 150)
Sarah spent twice as much as them150*2=300
altogether they spent $150+$300= $450
(just edited sorry for previous mistake)
Hi there!
The answer is <span>a) an arrangement of quantities whose positions are based upon the natural numbers
Your friend, ASIAX
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