Please help with the below question:

[Curtate Lifetime] Assume that lifetime 7 has probability density function f(1) = de d, fort 2 0, with A > 0. Let T, be the remaining lifetime of individual aged x > 0. Denote by K, the curtate lifetime defined as the integer part of Tx. That is to say that for an integer k 2 1, the two events (K, = *) and {k k). Hints for (c) and (d): Note that for |0)