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【单选题】
正弦信号的自相关函数是( )。余弦信号的自相关函数是( )。A.
同频余弦信号
B.
脉冲信号
C.
奇函数
D.
正弦信号
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皮皮学刷刷变学霸
举一反三
【单选题】Which has the higher strength and hardness in the follow microstructures? ( )
A.
sorbite
B.
troostite
C.
pearlite
D.
martensite
【单选题】A country which has a higher ratio of capital to other factors of production than does the rest of the world is:
A.
relatively capital-scarce.
B.
relatively capital-abundant.
C.
said to have a low capital-output ratio.
D.
operating at a point inside its production-possibility curve.
【单选题】Suppose that the interest rate is 6%. Which has the higher present value — a payment of $100 today or a payment of $112 two years from today?
A.
$100 today
B.
$112 two years from today
C.
there is no difference
D.
There is not enough information to determine the answer.
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