Researchers recruited a sample group of older adults and a sample group of younger adults for a study on memory. Their ages are below. Older adults: Younger adults: Age Age 2 Age Age 2 50 2500 22 484...

Researchers recruited a sample group of older adults and a sample group of younger adults for a study on memory.  Their ages are below.

Older adults:                                      Younger adults:
Age        Age²                                      Age        Age²

50           2500                                       22           484
72           5184                                       24           576
64           4096                                       30           900
78           6084                                       21           441
55           3025                                       26           676
84           7056                                       28           784
67           4489                                       27           729
65           4225                                       19           361
70           4900                                       32           1024

Calculate the mean, range, variance, and standard deviation for the ages of each group.