Answer :

When you put 10 to any power, you just get a one followed by the number of zeroes represented by the exponent:
8.1 x 10,000,000,000 = 81,000,000,000 
If you do not understand, you can always just use a calculator.
Hope this helps!
~Archim∈d∈sEl∈v∈n
according to siri its 10000000000 or 10^10