The ceo of a large automobile company says the cars the company makes are safe regardless of the fact that they lead the country in accidents due to faulty equipment. this discrepancy highlights which of the following critical thinking principles? a) few "truths" do not need to be tested.
b) all evidence is not equal in quality. c) authority or expertise does not make the claims of an authority or expert true. d) critical thinking requires an open mind.

Rate of return, standard deviation, coefficient of variation personal finance problem mike is searching for a stock to include in his current stock portfolio. he is interested in hi-tech inc.; he has been impressed with the company's computer products and believes hi-tech is an innovative market player. however, mike realizes that any time you consider a technology stock, risk is a major concern. the rule he follows is to include only securities with a coefficient of variation of returns below 1.07. mike has obtained the following price information for the period 2015 through 2018:hi-tech stock, being growth-oriented, did not pay any dividends during these 4 years. a. calculate the rate of return for each year, 2015 through 2018, for hi-tech stock. b. assume that each year's return is equally probable and calculate the average return over this time period. c. calculate the standard deviation of returns over the past 4 years. (hint: treat this data as a sample.) d. based on b and c determine the coefficient of variation of returns for the security. e. given the calculation in d what should be mike's decision regarding the inclusion of hi-tech stock in his portfolio?