Percentage investment in new-product development is monitored for a pharmaceutical company by quarter. The observations are listed rowwise:

(a) Can we conclude that the sequence of investment percentages is random? Use α = 0.05.

(b) Is there clustering? Is there a trend? Use α =0.05.

(c) Can you conclude that the distribution of investment percentages is normal? Use α = 0.01.

(d) Find a 98% confidence interval for the mean percentage investment.

(e) Find a 98% confidence interval for the standard deviation of the percentage investment.

(f) Can we conclude that the mean percentage investment in new products exceeds 31%? Use α =0.01. What is the p-value? Explain.

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