The term (maturity) of a forward rate agreement is 90 days and the underlying rate is 180 - day LIBOR. If 180-day LIBOR increases over the term (life) of the contract, which of the following best describes the descriptive notation for the contract and the party receiving payment at expiration, respectively Descriptive notation Party receiving payment at expiration ①A. 3 × 6Long ②B. 3 × 9Long ③C. 3 × 6Short

A．

B．

C．

简要说明光电式传感器的应用和特点。