In order to provide decision support for reasonable water pricing, this paper analyzes the water price leverage for the optimal arrangement of water resource, discusses the constituents and principles of water pricing, and forecasts the water price by water supply and demand model with the case study of Tianjin.

The paper discusses the impact of traditional reinsurance to stock income by introducing the leverageto the reserved capital of listed insurance companies, and demonstrates how to adjust the stock incomeby the change of rese.

According the calculating method of mortgage loan of merchandise housing, the purchaser should know that the time value of capital sum is calculated in the way of compound interest, so the purchaser should have a proper attitude to the leverage effect in mortgage purchasing.