In 2006, the mathematics scores of Weifang Academic Proficiency Test were announced by grade, and all candidates' scores were divided into counties (cities) from high to low.

(1) According to the meaning of the question, the total number of people selected is: 16+20+24+ 12+8=80.

The central angle of the sector is 360×1680 = 72,

Represents the fan-shaped central angle of B = 360× 2080 = 90,

Represents the fan-shaped central angle of c = 360× 2480 = 108,

Represents the central angle of the sector with d = 360× 1280 = 54,

Represents the fan-shaped central angle of e = 360×880 = 36°,

As shown in the figure:

(2) The number of Grade A students is 20%× 1320=264 (persons).

Class B population is 25%× 1320=330 (persons).

(3) The number of Class A and Class B is more than the average number of Class A and Class B in the whole city.

The number of class C people is the same as the average number of class C people in cities.

The number of people such as D and E is less than the average number of people such as D and E in cities.