Probability

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How do I get k from Probability Mass Function of a random variable x as; P(x) = K [2σ(x) + σ(x+1) + 3σ(x+2) + σ(x+3) + 2σ(x+4)] also I want to find the CDF of x and the mean from the PMF. Lastly, Draw the PMF and CDF And find p (x≤-2) from the CDF?