Is it the years  _______  you worked in Africa as a doctor  _______  have a great effect on your literary works?

A．that; where

B．that; that

C．when; where

D．when; that

在建设社会主义新农村的活动中，某村计划要硬化长6km的路面．

（1）求硬化路面天数y与每日硬化路面x（km）的函数关系式： _________ ；

 （2）若每日能硬化路面0.2km，则共需 _________ 天能完成施工任务．