Twelve samples, each containing five parts, were taken from a process that produces steel rods at Emmanuel Kodzi’s factory. The length of each rod in the samples was determined. The results were tabulated and sample means and ranges were computed. The results were:

SAMPLE SAMPLE MEAN (in.) RANGE (in.)
1 10.002 0.011
2 10.002 0.014
3 9.991 0.007
4 10.006 0.022
5 9.997 0.013
6 9.999 0.012
7 10.001 0.008
8 10.005 0.013
9 9.995 0.004
10 10.001 0.011
11 10.001 0.014
12 10.006 0.009

Determine the upper and lower control limits and the overall means for -charts and R-charts.

Stock a has a beta of 1.2 and a standard deviation of 20%. stock b has a beta of 0.8 and a standard deviation of 25%. portfolio p has $200,000 consisting of $100,000 invested in stock a and $100,000 in stock b. which of the following statements is correct? (assume that the stocks are in equilibrium.) (a) stock b has a higher required rate of return than stock a. (b) portfolio p has a standard deviation of 22.5%. (c) portfolio p has a beta equal to 1.0. (d) more information is needed to determine the portfolio's beta. (e) stock a's returns are less highly correlated with the returns on most other stocks than are b's returns.