Answer: 44 out of the 100 households threw away milk cartons;

(2) 10000×44%=4400 (households),

A: If 654.38+00000 families drink milk regularly, 4400 families throw away milk boxes.

(3)4400×90÷6

=396000÷6,

= 66000 (pieces),

A: The milk cartons thrown away in one year can be made into 66,000 rolls of paper.