Exams

When traveling in a vacuum, electronic waves from the electromagnetic spectrum all travel at the same speed. Velocity is speed with direction, so they would all travel at the same velocity, realtively speaking. But frequency and wavelength are quite different.

The one word substitute for "a person who is always dissatisfied" is malcontent.

Benjamin Franklin has long been credited with the invention of bifocal lenses and he was the first to wear bifocal lenses. He did not produce them himself but instead had some optician in London or France make them for him to overcome Presbyopia, a condition that Franklin suffered. He was tired switching between lenses for far and near sightedness. And that resulted in inventing Bifocal Lenses.

Brooks Koepka shot a final round 68 for 281 (+1) to win his second straight U.S. Open, one stroke ahead of runner-up Tommy Fleetwood, who closed with the sixth round of 63 in U.S. Open history.