下面哪种写法符合汇票对金额的要求( ) A. Pay to the order of A. Co. the sum of one thousand US dollars by installments. B. B. Pay to the order of A. Co. the sum of one thousand US dollars plus interest calculated at the rate of 8% p.a. from the date here of to the date of payment. C. Pay to the order of A. Co. the sum of one thousand US dollars only converted into sterling equivalent. D. Pay to the order of A. Co. the sum o fabout one thousand US dollars.