The random variable Y has the following probability distribution

The random variable Y has the following probability distribution.
-----------------
k   |Pr(Y=k)    |
----|------------
5   |0.17       |
10  |0.22       |
15  |0.39       |
20  |0.17       |
25  |0.05       |
-----------------
The random variables (3 - (Y/5))^2 has a probability distribution of the following form.

k   |Pr((3-(Y/5))^2 = k)|
----|--------------------
a   |   d               |
b   |   e               |
c   |   f               |
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Where the values of a,b and c are in increasing order.
(a) Find the values of a, b and c.
(b) Find the values of d, e and f.