LUSAKA, Zambia (AP) — Chinese Premier Li Qiang will start a two-day visit to the southern African nation of Zambia on Wednesday that will focus on the $1.4 billion refurbishment of a Cold War-era railway line to further improve China’s access to critical minerals. China is heavily invested in mining in Zambia, which is one of the world’s top producers of copper that is integral to the production of electronic devices. Li, who holds China’s No. 2 leadership position after President Xi Jinping,