(1)原式=(-112)×12+1
=-1+1
=0;
(2)原式=4-(-2+4)
=4-2
=2.
My old toy monkey always _______ me of my happy childhood.
A. provides B. suits C. reminds
如下图所示:pH=a的某电解质溶液,通直流电一段时间后,溶液的pH<a,则该电解质可能是
A.NaCl
B.CuSO4
C.NaOH
D.K2SO4