Answer:
To multiply decimals, first multiply as if there is no decimal. Next, count the number of digits after the decimal in each factor. Finally, put the same number of digits behind the decimal in the product.
If each inch is 40 miles then 7(40) = 280 and add the 1/4 which is 10 so the answer is 290
Answer: (a)
Step-by-step explanation:
Given
The points are
and 
The distance between two points
is given by

Apply the distance formula

Hence, option (a) is correct.
The algebraic expression is 9w.
Hope this helps!