A lawsuit filed this week in Washington, D.C., alleges that some of the world's largest technology firms knowingly engaged in the usage of child labor in Africa's cobalt mines. The suit was filed by nongovernmental organization International Rights Advocates and mentions Apple, Dell, Microsoft, Tesla and Alphabet, the parent company of Google, USA Today reports. Cobalt is an essential part of rechargeable lithium batteries that power many of the electronic devices that the listed companies sell. According to the suit, two mining companies — British company Glencore and Chinese company Zhejiang Huayou Cobalt — supplied cobalt to all of the...