Clarifying mask confusion: N95, KN95, KF94, double-masking

N95, KN95, and KF94 masks differ in where they’re tested and approved, and what type of straps they have, says Dr. Abraar Karan, infectious disease physician at Stanford University. Photo by Shutterstock.

There’s been a lot of mask confusion during the COVID pandemic. What’s the difference between N95, KN95, and KF94? Is double-masking with a cloth and surgical mask effective?  

Pandemic-induced stress hormones can weaken your brain cells’ connections — and your ability to execute daily tasks, stay focused, and carry on conversations. Mastering sleep and exercise can help.

Banks have long made billions of dollars annually by charging people when they overdraw their accounts. Consumer advocates argue that these fees are abusive and predatory.

HBO’s “How To with John Wilson,” now in season two, starts with a simple explainer and then delves into deep questions about life.