= = 0.25= 0.125=
- = - = + = + = 3- =
53= + = = + - =
+ = - = + = - =
+ = 2- = - = - + =
= = =
0.11= 0.217= =
①=
②=
③=
④=
15分=时 65dm2=m2
450mL=dm3 850dm3=m3
1时15分=时