[SmG Phoenix]

So for 1.c.
Probability of getting heads first then tails or tails first then heads does not matter, meaning the order is not important.
Therefore, probability of tails then heads is:
(2/5)*(3/5)
This is the same for heads then tails.
Then using the answer from a. we can get an overall equation of:
(2/5)*(3/5)*2+(2/5)*(2/5)
So, 0.48+0.16=0.64
2. 3/4 chance of red getting in any random spin.
Therefore (3/4)*(3/4)
which gives an answer of 0.5625
b. Probability is again similar to question 1.c
(3/4)*(3/4)+(3/4)*(1/4)*2
This gives an answer of 0.9375
c. This question is basically the inverse of the previous question.
Two methods can be used to approach this question.
The first is that we know a chance of any given event occurring is 1. Therefore, we can simply get:
1-0.9375=?
The previous calculation is the probability of everything else that can happen.
The other methods is simply (1/4)*(1/4)=?
Both answers come out to be 0.0625. I would personally use the first method and use the second for a proof check.
I hope this helps. I do Unit 1&2 Methods with an average of 90%! :D So ask me anything maths related and I do have Unit 3&4 Methods as well, but not as solid. I hope my language was not too difficult to understand.