What if every time you bought a bottle of Poland Spring or Evian water to quench your thirst, you first poured a third of it onto the street? Sounds wasteful and crazy, right? Well, that’s what happens to Philadelphia tap water—more than a third of it is lost in transmission. Reporter Carolyn Beeler went in search of the missing water. All that talk about tap water got us wondering: What should water taste like? So we tracked down a foremost expert in water flavor, Arthur von Wiesenberger to discuss why our water tastes the way it does.

Four words are fueling a major fight in the nation’s capital: “established by the state.” That short phrase is at the heart of a Supreme Court case (King v Burwell) challenging the subsidies people are receiving to pay for their insurance plans under Obamacare. We’re joined by health management and law professor Rob Field from Drexel University to discuss the intricacies of the arguments and hear his prediction for an outcome in June.

Andrew Cohen is a professor of engineering at Drexel University, and he helps researchers visualize how cells change over time with the help of a custom-built 3D movie theater. Cohen recently stopped by for a conversation with musician Keith Pierce from the band Northern Arms for the next chapter in our series “So What Do You Do?”

In the lead up to the release of Ken Burns’ upcoming PBS special “Cancer: The emperor of all maladies,” The Pulse is featuring a series of stories about cancer. In the first installment, reporter Todd Bookman takes us back to a discovery that linked cancer to genetics and fundamentally changed how we thought of the disease.

Also on The Pulse this week: an update on our Clear Health Costs initiative, a new play about kidney transplants, and imagining what the check might look like if restaurants billed customers like hospitals bill patients.