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.
Records for tax deductions taken. Length of time to keep, and why: Seven years. 1  The IRS has three years from your filing date to audit your return if it suspects good-faith errors.ength of time to keep, and why: From six years to permanently. 1  Keep all records documenting the purchase price and the cost of all permanent improvements -- such as remodeling, additions and installations.