An independent random sample is selected from an approximately normal population with unknown standa given sample size and confidence level. (a) n = 9, CL = 90% degrees of freedom critical value (b) n = 23, CL = 98% degrees of freedom critical value (c) n = 38, CL = 95% degrees of freedom critical value (d) n = 18, CL = 99% degrees of freedom critical value Type here to search to O 920 F ~ 9 0 ( ( ) hp mort sc delete home o/0 O O backspace num lock Z A O P W E R