麻疹的发病原因是( )
A．胎毒加疠气B．胎毒C．胎毒加风邪D．风邪E．麻疹时邪
参考答案：E
An airplane manufacturing company routinely builds fighter jets for the U. S. armed forces. It takes fourteen months to build one jet, and the government pays for them in installments over the fourteen-month period. Which revenue recognition method should be used（）
A. Installment sales method.
B. Completed contract method.
C. Percentage-of-completion method.
什么是地球物理勘探？
