How Protective Are Multilayered Cotton Masks Vidcast: https://youtu.be/IbrJaVthGac Just how well do face masks work to block the spread of virus. Researchers from Case-Western U and Ohio State University studied the dispersion of artificially-created d

Summary: How Protective Are Multilayered Cotton Masks Vidcast: https://youtu.be/IbrJaVthGac Just how well do face masks work to block the spread of virus. Researchers from Case-Western U and Ohio State University studied the dispersion of artificially-created d