You can put this solution on YOUR website!
The easiest way to solve this is by converting the terms into standard form and then placing them back into notation form.
9.8E-4 is the same as 0.00098 as the decimal moves 4 forward
2.1E2 is teh same as 210 as the decimal moves 2 back
3.1E-1 is the same as 0.31 as the decimal moves 1 back
multiply these to form one term
0.00098x210x0.31= 0.063798 because you are only given 2 significant digits you round to the 2nd placing in this case you round it up to 0.064
to get the term back into standard notation move the decimal back 2 places you get the answer