JAPAN MINISTER SAYS ABOUT 170 YEN APPROPRIATE International Trade and Industry Minister Hajime Tamura told a parliamentary session Japan's small- and medium-sized enterprises are seriously suffering from the yen's rise and can only stand levels around 170 yen. He also said he still believes a dollar exchange rate level plus or minus 10 yen from 170 yen would be within levels agreed upon last month in Paris by six major industrial nations. Finance ministers of Britain, Canada, France, Japan, the U.S. And West Germany agreed on February 22 to cooperate in stabilizing exchange rates around the current levels. The dollar had closed here at 153.77 yen on February 20.