Please help me with this algebra word problem: my question is how do you find the length of a side with the area of 820 square kilometers and then rounding to the nearest thousand

The following tables each show the amount of money, in dollars, in four different bank accounts over time. which table best represents an exponential relationship? a. years 1 2 3 4 5 account balance 1100.00 1350.00 1600.00 1850.00 2100.00 b. years 1 2 3 4 5 account balance 1100.00 1210.00 1331.00 1464.10 1610.51 c. years 1 2 3 4 5 account balance 1100.00 1210.25 1320.50 1430.75 1541.00 d. years 1 2 3 4 5 account balance 1100.00 1190.00 1340.00 1550.00 1820.00