Editor's Note: The following are questions received from viewers of "Mad Money," seen every day at 6 p.m. EDT on CNBC.

You like to focus on " best of breed" stocks, so what's your opinion of Peabody (BTU) - Get Report? -- David from Tampa, Fla.

James J. Cramer:

I like the coal industry, and Peabody is the biggest and best of the group. While the majority of my own energy investments are in more traditional oil and natural gas stocks, this company directly supplies utilities that are operating at record levels.

I own Microsoft (MSFT) - Get Report, Southwest Airlines (LUV) - Get Report, Sanmina (SANM) - Get Report and Newport International (NWPO) . Am I diversified?-- John from Kansas

James J. Cramer:

You have three of a kind in tech stocks. That's good in poker, but not a good idea for investing. You have decent companies in Microsoft and Southwest, but I would add an oil company to offset the latter's exposure to rising fuel prices. And while I think speculation is OK, I'd stay away from the sub-$1 stocks like Newport, especially those that trade on the Bulletin Board.

I've doubled my money in Magellan Midstream Partners (MMP) - Get Report. Should I keep holding on?-- Greg from Oklahoma

James J. Cramer:

This is a solid energy pipeline company that reminds me of

Kinder Morgan

(KMI) - Get Report

. In fact, both companies yield around 5.7%, and Magellan even has better earnings coverage of its dividend. That said, when I double my money in a stock, I like to sell half my stake and play with the house's money. Otherwise, I risk

being a pig and seeing my profits disappear.

What's your opinion of WellPoint (WLP) ?-- Thomas from California

James J. Cramer:

That's a solid health insurer, trading at a 52-week high. But you know me, I prefer

UnitedHealth Group

(UNH) - Get Report

, which I own for my charitable trust,

ActionAlertsPLUS, in this space. The company consistently posts the fastest earnings growth in the industry, but the stock also trades at just 18 times conservative 2006 estimates.

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clicking here

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