若a>b,则ac2______bc2.
∵何数的平方一定大于或等于0
∴c2≥0
∴c2>0时,ac2>bc2
c2=0时,则ac2=bc2
∴若a>b,则ac2≥bc2.
空腹时血糖浓度为()
A.4.61~6.11mmol/L
B.3.61~7.11mmol/L
C.3.61~6.11mmol/L
D.5.61~6.11mmol/L
E.3.61~8.11mmol/L