The accompanying table shows a portion of job satisfaction scores (on a scale of 0 to 100) categorized by a person's field of expertise.

Field 1Field 2Field 3

80.................76.................81

76.................73.................77

⋮....................⋮....................⋮

79.................67.................80

a. At the 5% significance level, can we conclude that average job satisfaction differs by field?

b. If significant differences exist, use Fisher's LSD method at the 5% significance level to determine which fields differ.