As we have mentioned before, TDC is the global leader in production and distribution of sodium hydrosulfide (NaHS) and is very familiar to pulp and paper mills worldwide. TDC's NaHS and NaOH products are building blocks you can not do without. I suggest you contact them today.

TDC is adding new production capabilities and service terminals. Want to know more? Visit TDC's website (click on "More" below). Tell them I sent you, please.

Regards,

Jim


Answer to last week's riddle: 31. The only candles that remain lit are the ones that have an odd number of state changes, for instance Candle 1, Candle 4, and Candle 9. The only candles that will have an odd number of state changes are those with an odd number of factors, and the only numbers that have an odd number of factors are the perfect squares. 961, the square of 31, is the largest perfect square less than 1,000, which gives us our final answer.

Last week's riddle asked: "1,000 people will walk along a pathway where there are 1,000 candles. The first person down the path lights all the candles. The second person extinguishes the even numbered candles. The third person changes the state of every third candle – that is, if the candle is lit, she extinguishes it, if it is out, she lights it. The fourth person changes the state of every fourth candle and so on. For example, the eighth candle is lit by the first person, extinguished by the second, lit by the fourth, and extinguished by the eighth. From the ninth person on, everyone else walks past it without changing its state. After the thousandth person walks down the path, how many candles are lit? "

This week's riddle: I keep my islands, my loops, and my dots close at hand. Where are they?