—You haven’t been to the West Lake, have you?

—____. But I will go there with my parents this summer vacation.

A．No, I haven’t

B．No, I didn’t

C．Yes, I have

D．Yes, I did

一油罐车的车箱容积为40m³，该车内装满石油，现要测出石油的总质量，某同学用一架天平和两个相同的小玻璃杯来测石油的密度．他测得玻璃杯倒一定量的水时，水的质量为50g，倒相同体积的石油时，杯中石油质量为46g．求：（1）石油的密度；（2）油罐车内石油的总质量．