解下列各题：
若不等式（a+1）x＞a+1的解集是x＜1，则a必满足什么条件？
解：∵不等式（a+1）x＞a+1的解集是x＜1，
∴a+1＜0，
∴a＜﹣1．
人步行的速度是( )
从下面方框中选出与下列各句中画线部分意思相同或相近，并能替换画线部分的选项。
My mother usually goes to work at ____ about 7:30 in the morning,John is a clever boy. He ____ does well in all the subjects,Dave's father was ill two days ago, so he had to ____ take care of him at home.Last night, Tom was not ____ in. He went to a movie with his friends.
Cu+Cu2+(未配平)。NH4CuS03与足量的lOmol·L-1硫酸溶液混合微热，产生下列现象：