Cited here are four unrelated cases involving marketable equity securities:
1. A noncurrent portfolio of available-for-sale equity securities with an aggregate market value in excess of cost; includes one particular security whose market value has declined to less than one-half of the original cost.
2. The balance sheet of a company does not classify assets and liabilities as current and noncurrent. The port folio of available-for-sale equity securities includes securities normally considered current that have a net cost in excess of market value of $2,000. The remainder of the portfolio has a net market value in excess of cost of $5,000.
3. An available-for-sale marketable equity security, whose market value is currently less than cost, is classified as noncurrent but is to be reclassified as current.
4. A company's noncurrent portfolio of marketable equity securities consists of the common stock of one company.
At the end of the prior year, the market value of the security was 50% of original cost, and this effect was properly reflected in a Valuation Adjustment account. However, at the end of the current year, the market value of the security had appreciated to twice the original cost. The security is still considered noncurrent at year-end.

Required:
For each of the cases, describe how the information provided affects the classification, carrying value, and income reported for that company's investment securities.