如图所示,电路是4位倒T型电阻网络D/A转换器。模拟开关S由输入数码Di控制(i=0,1,2,3)。当Di=1时,Si接运算放大器反相端,当Di=0时,Si将电阻接地。试求:
在慕尼黑,一根多昧腊肠卖2欧元;在波士顿的芬维公园(Fenway Park),一只热狗卖1美元。当汇率为每欧元1.5美元时,以热狗表示的多味腊肠的价格是多少?当其他条件相同。而美元升值为每欧元1.25美元时,相对价格会如何变化?与最初的情况相比,热狗相对于多昧腊肠是变贵了还是变便宜了?
In Munich a bratwurst costs 2 euros:a hot dog costs $1 at Boston's Fenway Park.At an exchange rate of $1.50/per euro.what is the price of a bratwurst in terms of hot dogs? All else equal.how does this relative price change if the dollar appreciates to $1.25 per euro? Compared with the initial situation,has a hot dog become more or less expensive relative to a bratwurst?
三层楼的自来水管道如图10-10所示,已知各楼层管长l=4m,直径d=60mm,各层供水口高差H=3.5 m,沿程阻力系数λ=0.03,水龙头全开时阻力系数ζ=3,不计其他局部阻力。试求当水龙头全开,供给每层用户的流量不少于3L/s时,进户压强pM应为多少?