So the total number of people is 4/(8%)=50.

Number of people in figure (2)B =50-4-20-9-5= 12.

The percentage of graph (1)B =1-8%-10%-18%-40% = 24%.

When & lt2> exceeds 4 hours, the proportion of DE is 18%+ 10%=28%.

1800*28%=504 people

"3" accounts for more than a quarter of the low-headed people who rely heavily on mobile phones and rarely use them. This shows that there are more and more low-headed people and their dependence on mobile phones is more serious. We call on everyone to stay away from mobile phones and cherish life.