影响人口分布的决定因素是（ ）
A：人类生产方式和经济活动
B：发展时间的长短
C：自然条件
D：战争和地区冲突
学习化学观察尤为重要。下面对一些实验的现象描述不正确的是（ ）
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?
“如果全中国人手拉手站在赤道上，就能环绕地球赤道40多圈”，这句话说明（ ）
求不等式组 1-2·x<1x+5>3x+1的整数解．
-- Mum, must I do my homework now?
-- No, you ______. You can do it after supper.
