【单选题】According to the author, technology is important because ______.
A.
resources on land are running short in ten years
B.
man can use it to explore the deeper sea
C.
it is a lot of fun diving into the sea
D.
ancient people used it to explore the sea
【单选题】一个电容器的耐压为250V把电接入正弦交流电路中使用时加在电容器上的交流电压有效值可以是( )
【单选题】需经适当加热,方可溶于氢氧化钠水溶液的萜所具有的基团或结构是
【单选题】需经适当加热,方可溶于氢氧化钠水溶液的萜具有的基团或结构是
【单选题】毛泽东曾评价哪位伟人德才兼备,军政皆优,是一位能够“上马击狂胡,下马草军书”的非凡帅才?
【简答题】先化简,再求值: ( a-1 a+2 - 1 a-2 )÷ a 2 -8a+16 a 2 -4 ,其中a=-3.
【简答题】算一算,写出英文数字。 1. 2 + 10 = __________________ 2. 16 + 18 = __________________ 3. 50 + 50 = __________________
【单选题】需经适当加热,方可溶于氢氧化钠水溶液的萜具有的基团或结构是