Cheng, R. , Liu, J. , Hao, L. and Wu, D. (2026) On the Application of the Infinitesimal Method to Two Categories of Problems in College Physics. Open Journal of Social Sciences, 14, 378-389. doi: ...

Global growth is projected at –4.9 percent in 2020, 1.9 percentage points below the April 2020 World Economic Outlook (WEO) forecast. The COVID-19 pandemic has had a more negative impact on activity ...