create an conceptual commemorative $50 bill featuring Martin Luther King Jr. on the front and the Lincoln Memorial on the back, with unique security features like color-shifting ink, a holographic strip, and a civil rights watermark.
创建一个概念性的50美元纪念性钞票,正面为马丁·路德·金,背面为林肯纪念堂,并具有独特的安全功能,例如变色墨水,全息条,还有一个民权水印。