A:5tan40°
B:5cos40°
C:5sin40°
D:5cos400
在某生态系统中,存在蛇、猫头鹰和鼠等动物.当猫头鹰也以鼠为食时,蛇与鼠、蛇与猫头鹰的关系是( )
The book ______ he bought yesterday is very interesting.
728×6=4368