....... ...................... cell phones overtook landline phones, and the services became equal in popularity with customers' annual expenditure of about $550.
In 2006
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10
What trend is this?
remain stable / unchanged
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25
What does teacher say you should do if you don't understand something in class?
Ask questions!
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25
What're your biggest goals for studying in this course? Why!
...
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15
Meanwhile, spending on residential phone services experienced a steep fall in 2007 and went on to................ ....................... for the rest of the period.