I've seen many contest that offers cars and even house as the grand prize and ppl actually won it. My question is do they need to pay tax on the prize?

Say a person win a car worth rm100k, does the person get taxed according to the value of the car?

How about if the person sold off the car and take the money, will it be taxed?

Actually for companies like Shell & Petronas, do frequently giv out cash prizes, bside attracting more ppl, do they get larger tax cut or something like that?