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Answer:
The answer is three fiths
Probability a gets a head = 1/2
.. .. .. b .. .. ... .. = P(a gets tail) * 1/2 = 1/2 * 1/2 = 1/4
.. ... . .. c .. .. .. .. . = P(and and b gets tail) * 1/2 = 1/4 * 1/2 = 1/8
I have no problem answering but it wont let me open the pdf. I will gladly give you your points back just thought that you should know