如图,∠1+∠B=180°,∠2=45°,则∠D的度数是( )
A:25°
B:45°
C:50°
D:65°
A woman____ ____ by a self-driving car as she walked her bicycle across a street.
人体免疫缺陷病毒(HIV)入侵T细胞后,T细胞死亡。以下有关说法正确的是
如图,在边长为1的小正方形组成的网格中,△ABC的三个顶点均在格点上,则tan∠ABC的值为( )
函数f(x)=x+3x的零点所在的区间为( )