二次函数y=ax²+bx+c (a≠0)中的自变量x与函数值y的部分对应值如下表：

则ax²+bx+c=0的解为____ ．

某烷烃碳架结构如图所示：，此烷烃的一溴代物有　____　种；若此烷烃为炔烃加氢制得，则此炔烃的结构简式为____　，若此烷烃为单烯烃加氢制得，则此烯烃的结构有____ 种（不考虑顺反异构）．

已知正整数a满足不等式组$\left\{\begin{array}{c}x\ge a+2\\ x\le 3a-2\end{array}\right.$（x为未知数）无解，则函数y=（3﹣a）x²+$\frac{1}{2}$x﹣$\frac{1}{4}$图象与x轴的交点坐标为____．

根据句意及首字母提示完成单词

① I usually go to school at h____ past seven.

② How many l____ do you have on Monday?

③ Class is over. Let's have a b____.

④ Her sister's favourite s____ is art.

⑤ I like listening to music. What a____ you?