a,7.1,6.8,5.6,3.2,2.5,2.5,0.3,1.2,1.4 It is known that the sample variance is 11.361 . (a) Find a. [9 marks ] (b) Suppose x1,x2,,x8 is another set of 8 measurements with sample mean 2.4 and sample variance 7.52. Find the mean, variance and standard deviation of the combined set of measurements. [6marks].