Rubbish should not ____ (throw) into lakes and rivers carelessly.
x
1
2
3
f(x)
有关下面四个国家地理特征的叙述,正确的是( )
观察下列各式:①abx﹣adx;②2x2y+6xy2;③8m3﹣4m2+2m+1;④a3+a2b+ab2﹣b3;⑤(p+q)x2y﹣5x2(p+q)+6(p+q)2;
⑥a2(x+y)(x﹣y)﹣4b(y+x).其中可以用提公因式法分解因式的有( )