Regarding Shershah Suri, which of the following statements are correct?

(A) To promote trade and commerce, Shereshah struck fine coins of silver and copper uniform standards in place of the debased coins of mixed metals of earlier times

(B) He also made some effort to standardize weights and measures

(C) In his empire, goods paid customs duty only two times - at the place of entry and at the time of sale

(D) He built a number of sarais which exclusively served as the resting places for the travellers only

Choose the most appropriate answer from the options given below :