A:a、d
B:b、d
C:b、c
D:a、c
某学生做如下实验:第一步,在淀粉KI溶液中,滴入少量NaClO溶液,并加入少量稀硫酸,溶液立即变蓝;第二步,在上述蓝色溶液中,滴加足量的Na2SO3溶液,蓝色逐渐消失。下列叙述中对实验原理的解释和结论不正确的是( )
—No, it be her. She has gone to Yunnan on holiday.
—How can we help the children in the mountain village?
—We can ____ leaflets to ask people to donate money.
已知向量a→=-1,1,b→=3,m,a→//(a→+b→),则m=( )