This is the 50th WhyGuy story. Happy semicentennial!

Why Guy started just under a year ago when I asked why is the Tower Bridge painted this color and exactly what is it? It's "metallic gold." CalTrans put it to a vote of the people and it wasn't even close. If you don't like the color, hang in there, its a 30-year paint job, so we can vote on this again in 2032.

Another Why Guy was spurred by a Facebook question from Leo who asked, "My hometown of Chicago has a great city flag, why doesn't Sacramento?"

Well, as it turns out, Sacramento does have a city flag, which rarely flies anywhere. A city staffer dug one out for us. It’s been the official Sacramento flag since 1989. He told us the flag is in "disuse."

Do you like it? It replaced the old school 1964 version. Maybe you don't like both.

Mary Kay asked Why Guy, "Why does my smoke alarm chirp in the middle of the night when the battery runs out?" The reason it chirps overnight is the temperature in your house drops and when a battery is dying, the cooler temp triggers the chirp — at 2 a.m.

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Then there's Terin, who sent us on a Why Guy road trip asking why there was a bunker on I-80 eastbound just before Maple in Auburn. We got access to what looked like a military bunker hideout and once we opened the doors, what we found was some kind of storm drain or electrical wiring with PVC pipe.

No exciting military bunker, so you're all safe to keep driving by on I-80.

We also drove to Ripon, where Cheryl asked us why there’s a flashing red light at a busy four way stop. Cheryl wants the lights on a traditional red, yellow, green cycle.

But we learned that heavy commercial traffic has worn out the sensors on the street, and the plan is to fix the sensors, and, at that point, get the traffic light off of the flashing reds.

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We've also been asked about city naming, which, let's be honest, we've all wondered at some point or another. Clifton asked why is Lake Tahoe named that?

To many people, the answer we found was surprising. It's only officially been named Lake Tahoe since 1945. Before that, it was called Lake Bigler, after the California Governor in 1854.

Another one of our favorites was why is Sacramento the state capital? It was in 1852, but lost it to Vallejo. And then we got it back in 1854. And kept it for the last 165 years.

So we have 50 Why Guys under our belt and a thousand more to go. If you have a why question, reach out to Walt on his Facebook page.

WATCH MORE: Walt Gray explains why every week on #MorningBlend10