3. Sixteen smokers whose ages were between 50 and 65 years were randomly selected. Blood samples were taken from them. Their cholesterol levels were determined and are presented below. 181 287 240 256 257 179 209 296 211 231 171 248 189 212 189 187 Compute the following: a. Sample mean b. Sample variance c. Sample standard deviation 4. The following are the scores in Math of the sampled 15 Grade 10 students: 60 61 58 70 62 74 75 78 80 68 85 86 80 65 70 Compute the following: a. Sample mean b. Sample variance c. Sample standard deviation