讲解下高中定语从句的这几道题

讲解下高中定语从句的这几道题1.we are living in an age____many things are done on computers.A.which B.that C.whose D.when2.Carol said the work would be done by October,____personally I doubt very much.A.it B.that C.when D.which希望以这两小题请大家讲一下when which that 的区别简单说下就好,不要太多了另外答案分别是D和B我自己打上去的啊