MELVILLE, N.Y. (AP) ¿ Park Electrochemical Corp. said Tuesday that its fiscal third-quarter profit more than doubled, helped by a lower tax rate and fewer charges compared with the year-ago period. The circuit materials maker earned $7.2 million, or 35 cents per share, up from $2.9 million, or 14 cents per share, in the same period a year ago. The prior-year period's results included a restructuring charge of $570,000. Sales slipped 6 percent to $46.1 million from $49.2 million for the quarter ended Nov. 29. Park's tax rate was 7.4 percent for the quarter compared with 33 percent a year earlier.