can you please help me out with this question please? this is not my homework, and no im not being lazy, just want to learn how to do it, for revision purposes. thank you

a pack of 16 cards contains 4 cards of each of the colors red,blue,green, and yellow.the four cards of each color are numbered 1,2,3 and 4.

i)the pack is shuffled and is drawn at random, find as a fraction that it is a red card numbered 4 or a blue card.

ii)The card is replaced, the pack is shuffled again and two cards are drawn at random. Find as a fraction the probability that

a)they are both yellow

b)at least one is blue.

for number I), i was able to solve it by going (1/4*1/4 + 1/4)=5/16

BUT its the ii) that im stuck.

Appreciate the help.