阅读下列材料，回答问题。

    玫瑰喜冷怕热，爱阳忌阴、耐肥畏瘠，喜爱水足肥丰、排水性能好的土壤。

厄瓜多尔是世界最适合玫瑰生产的国家之一，现有100多个玫瑰品种，已成为世界第四大玫瑰生产国，顾客遍及世界各地。该国的玫瑰农场主要分布在中北部海拔3000多米的科多帕希火山（海拔5896米）周围地区。

如图所示，两个质量相同的物体A和B紧靠在一起，放在光滑的水平桌面上，如果它们分别受到水平推力F₁和F₂作用，而且F₁＞F₂，则A施于B的作用力大小为(　　)

    Mrs．Marks bought a printer yesterday．She was h____ because she could print anything she wanted at any time．H____,after about an hour, she was angry because she couldn't print the color blue．All the other c____ printed free, except(除了)blue，which was very unusual．

    She d____ to call the after-sales service department(售后服务部)to help her solve the problem．David answered the phone．He t____ everything he could think of to help Mrs．Marks．He asked her to reinstall(重新安装) the program，to reboot (重新启动)the computer and to turn the printer on and off．N____ of these things helped．

After hours of trying，the problem s____wasn't solved．Finally, David asked Mrs．Marks if he could go to her h____and try to solve the problem in  person．Mrs．Marks agreed and t____ him her address(住址)．When he arrived at her house，she showed him her computer and the printer. David u____what the problem was right away．He told her,“From now on，print on white paper instead of blue!”