The National Safety Council reports the following age breakdown for licensed drivers in the United States. Source: Bureau of the Census, Statistical Abstract of the United States 2009, p. 682 . Age...

The National Safety Council reports the following age breakdown for licensed drivers in the United States.

Source: Bureau of the Census,

Statistical Abstract of the United States 2009,

p. 682.

Age (Years)         Licensed Drivers (Millions)

Under 20                             10.72

20–under 25                       16.84

25–under 35                       40.78

35–under 45                       45.59

45–under 55                       36.70

55–under 65                       23.32

65 or over                           28.76

Identify the following for the 35–under 45 classes:

(a) Frequency (b) upper and lower limits (c) width and (d) midpoint.