Answer:
def waterBill(gallons: int):
if gallons < 8001:
return 5*(gallons/1000)
elif gallons > 8000 and gallons < 22001:
return 6*(gallons/1000)
elif gallons > 22000 and gallons < 30001:
return 7*(gallons/1000)
else:
return 10*(gallons/1000)
print(waterBill(5000))
print(waterBill(28000))
print(waterBill(40000))