360÷8÷3= 15 Parts that a machine tool can process in one hour.

1350/615 =18 hours. It takes 18 hours.

2、

600-440 =160g two glasses of water.

A glass of water 160 ÷ (5-3) = 80g.

I hope to learn by going up a flight of stairs. If you don't understand, you can ask questions and ask for adoption ~