微分方程的特解可设为（）
________they'vegottoknoweachotheralittlebetter,theygetalongjustfine.
大脑半球表面存在的大沟裂有
heteachertoldthemsincelight________(travel)fasterthansound,lightning________(appear)togobeforethunder.
ShegotajobasanassistantstagemanagerattheCambridgeArtsFestivalTheatre,thinkingthatitmight________toacareerasaplaywright(剧作家).
，其中n为正整数,则f'(0)=()