Contrary to what we had expected, the noodles and rice they served on the plane __________ quite delicious.
A:are
B:is
C:were
D:was
如图,AB是⊙O的直径,弦BC=2cm,F是弦BC的中点,∠ABC=60°.若动点E以2cm/s的速度从A点出发沿着A→B→A方向运动,设运动时间为t(s)(0≤t<3),连接EF,当△BEF是直角三角形时,t(s)的值为( )
— Do you mind my parking here? The parking lot is full.— ______. Look at the sign! It says, “No Parking!”
关于电磁波,下列说法正确的是( )
下列四个式子中,是一次多项式的是( )