degree centigrade 是否有复数形式

Hello!Degree centigrade是摄氏度还是Centigrade degree是摄氏度?还有,什么情况下degree加s?thanx!

1.Water______(freeze)at the temperature 0 degree centigrade.
2.The young student________(experience)many hardships in the past few years.
3.After doing a lot of experiments,the scientist___(have)a rest.
4.Madam Curie______(engage)her whole lifetime to the scientific research.
5.He_______(continue)writing his diaries until he died.
6.The book is so _______(instruction)thast it is worth reading twice.
7.I joined the army ladt year.(句意不变)
I ____ ____ ___ the army for a year.
8.How is thw weather today?
_____the weather____ today?
9.已知在等边三角形abc中,dc=ae bq垂直ad于q(b c d 不重合)
求证 bp=2pq
10.在三角形abc中,角a:角b:角c=4:2:1 ad平分角bac
求证:ad+ab=ac