在横线上填入正确的颜色单词。

                                                       What color are their l. _____?

      Kate, Jim, Rose and Bill put their sweaters on the table. The sweaters are white, blue, red and

black. We know, the boys' sweaters aren't red and the girls' sweaters aren't black. What color is

Kate's sweater? I don't know. But I know Kate doesn't like blue. Bill says, "My sweater is white. "

Then what color are their sweaters?

2. Kate's sweater is _____.                      

3. Rose's sweater is_____.

4. Jim's sweater is _____.                  

5. Bill's sweater is_____.

每次使用pH计和电导率仪进行测量时，仪器接通电源后，均应进行预热，预热的时间为________分钟。

A．10

B．20

C．30