The pact had allowed Iran to enrich uranium at a 3.67 percent concentration level.

该核条约允许伊朗浓缩铀丰度限制在3.67%。

The Dead Sea, which has a 33 percent concentration of salts and minerals, is located at the lowest point on Earth, 390 meters below sea level.

死海中盐和矿物质的浓度是百分之三十三，它位于世界上的最低点：低于海平面三百九十米。