【单选题】She has a small machine for ____ coffee beans.
【单选题】与无创血压相比较,有创血压监测的优点不妥的是?
【单选题】下列各组中,互为相反数的有: ① ②-(-6),+(-6) ③ ④ [ ]
【单选题】She is an accomplished athlete and won the championship four times ( ).
【简答题】先化简再求值: a 2 -4 a 2 +6a+9 ÷ a-2 2a+6 -2 ,其中a=1.
【单选题】与无创血压相比较,有创血压监测的优点不妥的是
【简答题】(1)计算: ( 3 -2 12 - 6 )?2 3 +5 2 (2)解方程组: x+2 =y x-2y=1 .
【简答题】(1)计算:|-2|+2sin30°-(- ) 2 +(tan45°) -1 . (2)先化简,再求值:2(a+ )(a- )-a(a-6)+6,其中a= -1.
【简答题】She is an accomplished athlete and won the championship four times ( ) ( ).