Steele Corp has the following annual returns for the previous four years: 20%, 25%, 30%, 50%. Calculate Steele Corps average return, sample variance and sample standard deviation.

average 31.25%; sample variance 518.75; sample standard deviation 22.78%

average 125%, sample variance 13.33, sample standard deviation 3.65%

average 31.25%; sample variance 172.92; sample standard deviation 13.15%

average 125%, sample variance 518.75, sample standard deviation 22.78%