War Veteran, Squash, Mass Shootings

Hosted by Jane Pauley. In our cover story, David Pogue rides a submersible to the wreck of RMS Titanic. Also: David Martin profiles a wounded Ukraine veteran who travels to the U.S. for a prosthetic leg; Martha Teichner examines how mass shootings are being memorialized; And Allison Aubrey meets a chef and a vegetable breeder who set out to create a better-tasting squash.