1. A biased coin is tossed until the same result appears three times in a row (i.e., three heads or three tails in succession). Letpdenote the probability the coin comes up heads, 0< p <1. Find the probability that the game will end at the seventh toss. The tosses are independent.
2. The biased coin from problem 1 is tossed until a head appears for the first time. What is the probability that the number of tosses required is even?

Attention: it is a biased coin at first I think it follow a Geometric distribution and p=0.5, so answer for question 1 is 0.5^6*0.5=0.0078125,but it is a biased coin so p not equal 0.5 right? so what should I do next? plz tell me thx.