To calculate the current in a circuit, we can use Ohm's Law, which states that the current (I) flowing through a circuit is equal to the voltage (V) divided by the resistance (R). So, in this case, the current would be:
I = V / R
I = 9.0V / 5.00 ohms
I = 1.8 A
So, 1.8 A of current would flow in a closed circuit that has a 9.0V battery and 5.00 total resistance.