Determine whether the given argument is valid. For the valid argument, construct a formal proof. o. Zoilo took either the bus or MRT. If he took the bus or drove his own car, then he arrived late and...

Determine whether the given argument is valid. For the valid argument, construct a formal proof.

Extracted text: o. Zoilo took either the bus or MRT. If he took the bus or drove his own car, then he arrived late and missed his first class. He did not arrive late. Therefore, he took the MRT.