In scientific notation, 330 is written?

3.3 x 10^2

When you convert a number to scientific notation, you have to move the decimal right or left so that the whole number falls between 1 and 10.  You then "describe" what you would multiply by to get the original number by multiplying by 10^x.  x is the number of decimal places you moved.  If you move the decimal to the left, it will be a positive exponent.  If you move the decimal to the right it will be a negative exponent.  Here are some examples...

10,000 = 1 x 10^4
0.0001 = 1 x 10^-4