【单选题】598×□<2400,□里最大能填( )
【简答题】估算. 598×42≈ 302×39≈ 253×42≈ 91×508≈
【单选题】下列压强单位换算中错误的是()。
C.
1kgf/cm 2 =1.0133*10 5 Pa
【判断题】when going up after the racoon, the branch Jerry was standing cracked and he fell into the deep hollow of the dead tree.
【简答题】42的7倍约是______,598约是6的______倍.
【简答题】根据485+598=△,写两道减法算式:______;______.