Central asia is bordered by in the north and in the east. a. russia . . china b. the caspian sea . . china c. the caspian sea . . russia d. lake balkhash . . caspian sea

A.
Russia . . . China

Central Asia is bordered by Russia in the north and China in the east.

Russia sits directly on top of Kazakhstan and China on it's right. 

Central Asia is bordered by Russia in the north and China in the east.

Explanation:

The entire northern part of Asia is spanned by Russia. It is because of its east-west expanse, all the countries that form the central belt of the mainland Asian continent share their northern borders with Russia. The eastern part of Asia begins with the western boundary of China. Thus the countries that come in Central Asia share their eastern boundaries with China.

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.

F=31 because you subtract 39-8