在有N个缓冲区的生产者消费者的问题中，下列叙述中哪些是错误的？producer() { int item; while(TRUE) { item = produce_item(); P(empty); P(mutex); insert_item(item); V(mutex) V(full); } } consumer() { int item; while(TRUE) { P(full); P(mutex); item = remove_item(); V(mutex); V(mutex); consume_item(item); } } A: 信号量empty的初值为N B: 信号量full的初值为0 C: 信号量mutex的初值为0 D: P(full)和P(mutex)两条语句可以颠倒顺序 E: V(mutex)和V(mutex)两条语句可以颠倒顺序

开启第二条生产线的标准（） A: 早餐ITEM数≥280/午餐ITEM≥241 B: 早餐ITEM数≥281/午餐ITEM≥240 C: 早餐ITEM数≥241/午餐ITEM≥280 D: 早餐ITEM数≥200/午餐ITEM≥180

The opportunity cost of an item is ( ). A: the price of that item B: what you give up to get that item C: the time you have to spend on earning enough money to buy that item D: the cost of producing that item

A credit item is an item for which a country must pay. ( )

What is true about the point-to-point comparison? A: We move back and forth between Item A and Item B at each point. B: We should discuss items in the same order throughout the essay. C: Shifting between Item A and Item B makes the comparison easy to follow. D: It fully discusses Item A at first and then turns to Item B. E: It presents all the information about Item A and then all that about Item B.

Which is not the content of Micro-economics A: Full employment B: What to produce C: How to produce D: Whom to produce fo

If an item is _________ the shopping cart, chances are your item is sold out.

The most effective complaint can be made by ________. A: showing the faulty item to the manufacturer B: explaining exactly what is wrong with the item C: saying firmly that the item is of poor quality D: asking politely to change the item

3. What is true about the point-to-point comparison? A: We move back and forth between Item A and Item B at each point B: We should discuss items in the same order throughout the essay C: It presents all the information about Item A and then all that about Item B D: Shifting between Item A and Item B makes the comparison easy to follow

When defining an item, one no longer needs to specify the features of the item as long as one has already explained what category the item belongs to.