①胰岛素分泌量对血糖浓度的影响 ②运动强度对汗腺分泌的影响
③降雨量对土壤动物存活率的影响 ④害虫数量对其天敌鸟类数量的影响
A:①②
B:②③
C:③④
D:①④
实验室欲用NaOH固体配制1.0mol•L﹣1的NaOH溶液230mL:
下列等式正确的是( )
Protect Wild Animals
Animals are our good friends.We live in the same Earth.Animals and people can't be separated from each other.But some animals are getting less and less.So it's important to us to protect animals,especially wild animals.Some people kill wild animals because of money.It's wrong.Now people need more places to live in.We explore the forest. Animals have less places to live in.The number of wild animals decreases year by year.So we should protect wild animals.
关于电场线,下述说法中正确的是( )