引用集合中的数据项需要使用（）方法。 A: Clear B: Remove C: Contains D: Item

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

类JMenu的常用方法中删除菜单的所有菜单项的方法是（） A: getItemCount() B: insert(JMenuItem item,int n) C: remove(int n) D: removeAll()

‎类JMenu的常用方法中删除菜单的所有菜单项的方法是（）​ A: getItemCount() B: insert(JMenuItem item,int n) C: remove(int n) D: removeAll()

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.

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

Heat the soup for ten minutes, and then _______from the stove. A: you should remove it B: removing it C: to remove it D: remove it