How do you express this in scientific notation: 80,300,000,000

Can some one me, i’ve been asking for so long

Asquare parking lot has 6,400 square meters what is the length in meters

Pepe and leo deposits money into their savings account at the end of the month the table shows the account balances. if there pattern of savings continue and neither earns interest nor withdraw any of the money , how will the balance compare after a very long time ?