Ethan had a headache, so he took 2 tablets of acetaminophen (325 mg each) at 1:00 pm. Suppose acetaminophen is eliminated from the body at a continuous decay rate of 24% per hour. Right before Ethan takes another dose at 7:00 pm, about how many milligrams of acetaminophen are still in his body from the dose he took earlier in the day?