A：日心说的代表人物是托勒密
B：丹麦天文学家第谷通过对行星运动的观测研究得出了行星运动的规律
C：牛顿发现了万有引力定律，并测出了引力常量的数值
D：海王星是“笔尖下发现的行星”
CaCO3+2HCl ==== ____ + ____ + ____
People ran out __________ as fire tore through the building.
根据句意和首字母提示完成下列句子。There are sixty m____ in an hour．He is ill, and his i____ makes us feel sad．A lot of t____ are visiting the Great Wall, so it is very crowded．Good food and e____ help me to study better．It is n____ to eat a balanced diet.
