Write 8.54 x 103 in standard notation
a. 854,000
b. 85,400
c. 8,540
d. 854

B. 8540, (assuming you meant 8.54 x 10 to the power 3) you move the decimal point 3 places to the right, if the decimal point can't pass any more numbers add zeros. If it confuses you to think of it this way do 10 cubed first, i.e. 10 x 10 x10 = 1000 and then do 8.54 x 1000 if thats easier for you.

Iwould say a is accurate