Swedish climate activist Greta Thunberg hit back at Steven Mnuchin on Thursday, after the Treasury Secretary suggested she needed to study economics in college before lecturing the U.S. on fossil fuel investments. “My gap year ends in August, but it doesn’t take a college degree in economics to realise that our remaining 1,5° carbon budget and ongoing fossil fuel subsidies and investments don’t add up,” the 17-year-old said via Twitter. “ So either you tell us how to achieve this mitigation or explain to future generations and those already affected by the climate emergency why we should abandon our climate commitments,” she added. Mnuchin had criticized Thunberg’s financial credentials at the World Economic Forum earlier in the day. Speaking to reporters during a press briefing, Mnuchin was asked whether the world’s largest economy should completely and immediately divest from fossil fuels. That’s because Thunberg, alongside 20 other young climate activists, had called on the world’s decision-makers and business leaders to stop all investments in fossil fuel exploration and extraction. “Is she the chief economist or who is she? I’m confused,” Mnuchin said, before adding this was “a joke. That was funny.” “After she goes and studies economics in college she can come back and explain that to us,” Mnuchin said. To view the full article visit CNBC.