30585 The life span of 1800 light bulbs is normally distributed with a mean of 900 (b) (a) (i) more than 1200 bours; (ii) between 600 and 1050 hours. (b) A continuous random variable z has a...

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Extracted text: 30585 The life span of 1800 light bulbs is normally distributed with a mean of 900 (b) (a) (i) more than 1200 bours; (ii) between 600 and 1050 hours. (b) A continuous random variable z has a probability density function f(1) defined be Ke,20 f(z) 0, elsewhere Determine: (i) value of constant K; (ii) mean%3B standard of the of light with life span