Right 720,080 in expanded form and in exponents

Expanded form: 720,080 = 700,000 + 20,000 + 80

To write in exponential form, it's easier to write it out.
700,000 + 20,000 + 80.
700,000 = 7 x 10^5 (the exponent equals how many zeros there are.) 
20,000 = 2 x 10^4 (There are 4 zeros so the exponent is 4)
80 = 8 x 10^1 (There are 1 zero so the exponent is 1) 

Exponential form: (7 x 10^5) + (2 x 10^4) + (8 x 10^1)