Here are returns and standard deviations for four investments.

	Return	Standard Deviation
Treasury bills	5.0%	0%
Stock P	11.5	16
Stock Q	14.5	28
Stock R	24.0	27

Calculate the standard deviations of the following portfolios.

a.	50% in Treasury bills, 50% in stock P. (Do not round intermediate calculations. Round your answer to 2 decimal places.)

Standard deviation

%

b.	50% each in Q and R, assuming the shares have: (Do not round intermediate calculations. Round your answers to 1 decimal place.)

	Standard Deviation
Perfect positive correlation	%
Perfect negative correlation	%
No correlation	%