What is the probability of drawing at random on the first draw?

a) a red ball from a bag containing 9 balls of which are red?

b) a black bean from a bag containing 24 beans of which 18 are black?

c) a marked card from a box containing 12 cards of which 4 are marked?

d) a green marble from a hat containing 30 marbles of which 18 are green?

Hindi po sia pagpipilian, the only question is beside the letters. ​