【简答题】f(t)[ε(t+1)-ε(t-2)]表示从信号f(t)中截取t=____到2的一段信号
【单选题】“'Painting!' she .. . 'What fun. But what are you waiting for? Let me have the brush — the big one.' She ... the paints and ... , she had ... several ... ... and ... of blue on the ... ... canvas .
A.
strokes...slashes...firce...swept...declared...before I knew it...plunged into...absolutely...terrified
B.
slashes...declared...before I knew it...plunged into...swept...absolutely...firce...strokes...terrified
C.
declared...plunged into...before I knew it...swept...firce...strokes...slashes...absolutely...terrified
D.
absolutely...slashes...strokes...declared...plunged into...before I knew it...swept...firce...terrified
【简答题】对话理解。 ( ) 1. A. Yes, she does. B. Yes, she doesn't C. No, she does. ( ) 2. A.Tom B. Lingling C. John ( ) 3. A.Tony B. Jim C. Ling Ling ( ) 4. A. play the s B. get on the photo ...
【简答题】《安全生产法》所指的危险物品包括哪些能够危及人身安全和财产安全的物?
【简答题】1)画出下列信号的波形 (1) f1(t)=2ε(t+1)-3ε(t-1)+ε(t-2) (2) f2(t)=r(t)-2r(t-1)+r(t-2) (3) f3(t)=sin(πt)[ε(t)-ε(t-1)] (4) f1(k)=k[ε(k)-ε(k-5) (5) 2)写出下列连续波形的表达式 3)写出下列离散波形的表达式 4)已知连续信号f(t),画出运算后的波形: (1)f(2-...