(2014? Quangang District Quality Inspection) Reporter Xiao Zhang wanted to understand citizens’ opinions on “the main causes of haze weather” and randomly surveyed some citizens in a certain district

(1) The total number of people is: 80÷20%=400,

m=400×10%=40,

n=400-80- 40-120-60=100,

(2) The percentage of option E in the fan chart is 60400×100%=15%;

(3) 40×120400 =12 (thousand)

Answer: It is estimated that the number of citizens in the district who hold the "viewpoint" of option D is 120,000.

So the answer is: (1) 40,100; (2) 15%; (3) 120,000 people.