请根据图中的信息,回答下列问题:
⑴The man is falling down the stairs.____
⑵The birds are flying away.____
⑶She is getting off the bus____
⑷My mum is on the phone.____
⑸They are having a birthday party.____
A. B. C. D. E.
某反应为2X+2SO2+O2→2CaSO4+2CO2,X的化学式是( )
若|a﹣ 12 |+(2b+1)2=0,则a2+b2的值为( )