this process helps to concentrate the urine and increase the volume of water in the blood. Aldosterone acts via a similar method as it acts to increase the production of 3 types of channels: 1) sodium channels.
This means that a new greenhouse costing $20,000 which has a useful life of 25 years would be depreciated at a rate of 8%, twice the straight line rate, of the undepreciated value each year as compared to taking 4% of the original cost each year as the annual depreciation allowance.
Some concentration of greenhouse gases in the atmosphere is normal, and in fact necessary for life on Earth as we know it. It is normal for the concentrations of these gases to fluctuate over time, causing the average global temperature to vary over a period of hundreds of thousands or millions of years.