【单选题】Some firms have cut workers’pay below the level set in their contract, a _______ that is illegal in Germany.
【单选题】Ad man Rosser Reeves believes that firms should develop a USP for each brand and stick to it. For what does USP stand?
A.
unique selling proposition
B.
universally strategic practice
C.
unique services practice
E.
unique selling product
【单选题】在商业广播电视图像信号中,广泛应用的线性调制是 ( ) 。
【简答题】相同情况下,AM、DSB-SC、SSB、VSB、FM这5种调制系统中,有效性最好的是_______,有效性最差的是_______,可靠性最好的是______。
【单选题】It is stated in the passage that__________.
A.
the United States is the first country to practice public relations
B.
some public relations firms have only one person
C.
there are more public relations firms in the U.S. than in any other place in the world
D.
a large percentage of employees in public relations work in profit-oriented sectors.
【判断题】AM, DSB-SC, SSB, VSB can use coherent demodulation.
【判断题】为了提高AM系统的调制效率,可采用DSB-SC调制;为了提高DSB-SC系统的有效性,可采用SSB调制;SSB设备复杂,存在技术难点,而VSB调制的滤波器较容易设计。
【判断题】DSB-SC、常规AM、SSB、及VSB系统的系统增益均是解调增益的一半。
【判断题】DSB-SC、常规AM、SSB、及VSB系统的系统增益均是解调增益的一半。