Procedure. 1  Start with a short lecture on the nature of solid, liquid, and gaseous water. 2  Your goal is to give some understanding that water molecules themselves don't change when the state of the matter changes, but that the interaction between molecules changes.
Check out our guide of what to toss when. Is your important paperwork piling up? Check out our easy-to-use chart to see what to keep, what to toss, and how to store those hard-to-replace documents. Keep tax returns, as well as supporting documents like W-2 forms, receipts, and real estate closing statements for seven years.
The IRS says you must keep your records as long as they may be needed to prove the income or deductions on a tax return. For example, determining gain or loss on a sale or disposal of an asset, you will need to substantiate the cost, so records and receipts related to that asset must be kept as long as asset is still in service and then add 3 years. The IRS says the length of time to retain business documents varies depending on how honest and how accurate your tax returns have been. If you file a fraudulent return, you must keep records indefinitely..