=________.
请填空:
(1)=________;
(2)=________;
(3)=________;
(4)=________.
计算:=________;=________.
如图,因为AB∥CD,所以∠A+________=180°(________);因为BC∥AD,所以∠A+________=180°(________).所以∠B=________.
如图所示,直线AB、CD相交于点O,∠AOD=130°,则∠BOC=________,∠AOC=________,∠BOD=________.
如图,直线AB、CD相交于点O,若∠1=28°,则∠2=________.
正数的相反数是_____,一个数的相反数的相反数是_____.
(1)有理数的运算顺序:先算_______,再算_________,最后算_________.如果有括号,要先算_______.
(2)对于同级运算要按_________运算.
,底数是______,指数是______.
-7的倒数是_______,-0.2的倒数是________.