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Plz 20 points polynomials 1: subtract and simplify (–y^2 – 4y – 8) – (–4y^2 – 6y + 3) 2: multiply and simplify 2x^2 y^3 z^2 · 4xy^4 x^2 3: multiply and simplify (x – 4) (x2 – 5x – 6)

Summary statistics given for independent simple random samples from two populations. use the pooled t-interval procedure to obtain specified confidence interval. x1=71.6, s1=3.9, n1=11, x2=67.9, s2=3.4, n2=9 determine a 99% confidence level.

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