A study of the relationship of between age and various visual function reported the following observations on area scleral lamina (mm2) from human optic nerve heads ("Morphometry of nerve Fiber Bundle Pores in the Optic Nerve Head of the Human," Experimental Eye Research) 2.75 2.62 2.74 3.85 2.34 2.74 3.93 4.21 3.88 4.33 3.46 4.52 2.43 3.65 2.78 3.56 3.01

a) Calculate the mean value. b) Calculate the sample variance and then the standard deviation

If clear I will give upvote