<image> To address the issue of air quality pollution, City A and City B have implemented comprehensive measures to manage environmental pollution in and around their cities. During the process, the environmental protection departments monitor the air quality of both cities at the beginning of every month for 10 consecutive months, as shown in Figure 1. The air pollution index classifications are as follows: air quality is excellent when the air pollution index is ≤ 50; good when 50 < air pollution index ≤ 100; and slightly polluted when 100 < air pollution index ≤ 150.

(1) Please complete the following table:
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(2) Please answer the following questions:
(i) Analyze the air quality of City A and City B using the mean and median.
(ii) Analyze the air quality conditions of City A and City B using the mean and variance.
(iii) Based on the trend of the air pollution index in the line chart and the excellent air quality conditions, analyze the effectiveness of environmental pollution management in both cities.