因式分解:a3+2a2+a=( )
a(a+1)2
There is no doubt ______ everyone will unite and work for better days.
A.whether
B.that
C.what
D.how
下列符合级Ⅰ粉煤灰技术要求的是()。
A.细度(45μm方孔筛筛余)≤12%,需水量比≤105%,烧失量≤5%
B.细度(45μm方孔筛筛余)≤25%,需水量比≤105%,烧失量≤8%
C.细度(45μm方孔筛筛余)≤45%,需水量比≤115%,烧失量≤15%
D.细度(45μm方孔筛筛余)≤12%,需水量比≤95%,烧失量≤5%