Cameras or mirrors in the front of vehicles

Notice that when exiting this parking lot just to see cars coming down the road half of your vehicle has to stick halfway out into the lane due to not being able to see through the parked cars! (posted speed limit is 30mph, but vehicles typically travel faster than that.)

https://www.google.com/maps/@32.8698966,-117.233749,3a,89.9y,137.32h,54.45t/data=!3m6!1e1!3m4!1syTOgwwzuE8VnmnDWT9kZXQ!2e0!7i13312!8i6656

This is because people's eyes are in the middle of the vehicle. One solution would be to have mirrors or cameras on the front of the vehicle. Or having a mirror in the middle road island. Or being to access nearby cameras mounted on say light posts.

Designing containers for smooth pouring

I'm sure many have noticed that when pouring liquid bottles it comes out in big clumpy waves. One wouldn't need a funnel if they'd design these things with proper airflow in mind to fill up space vacated by the liquid. Either use larger diameter spouts, or have another spout for air intake while liquid pours (as seen in a few liquid detergent bottles.)

Layers of tunnels to add traffic lanes

After the https://en.wikipedia.org/wiki/Interstate_Highway_System little has been done to significantly improve traffic flow. The populations have ballooned while road lanes have not.

Many places were designed street widths for a certain amount of traffic. The streets are now adjacent building locked so they can no longer widen them to accommodate the massive amount of traffic during the rush hour.

Since lateral road expansion isn't possible without razing buildings, we are left with vertical expansion. Going up with say double decker roads would be unsightly, no one would go for that. This leaves underground tunnels as the only real solution for adding more lanes. Only so many opt for mass transit such as buses and trolleys, many want the freedom and flexibility that automobiles afford

So much talk about housing crisis with little mention of the associated traffic crisis. People also need more lanes not just more houses. Less time on roads means more time to be productive. I suppose self driving cars will make waiting in traffic more bearable in the mean time as you'll then be able to do many of the things you'd do when you got home, such as check email.

Slightly north is the quickest way south

Ever wonder why the Sun sometimes appears to the north of your location even though the sub solar point https://en.wikipedia.org/wiki/Subsolar_point is at a lower latitude from your location? One must remember that the initial direction is just that; initial. A straight line on the globe follows a great circle https://en.wikipedia.org/wiki/Great_circle . Unless that great circle follows a line of longitude or the Equator, the path direction along each point of that great circle changes. Great circles are basically the same as https://en.wikipedia.org/wiki/Orbital_inclination where if you keep going it bounces between a northern and southern latitude line.

4.9 mega meter distance example
Cabo San Lucas: +22.9 lat -109.9 lon
Honolulu: +21.3lat -157.8lon

A straight line path from Cabo has an initial heading of 277.6 deg (7.6 deg north of west) even though Honolulu is at a lower latitude (1.6 deg lower.) The great circle path will actually reach up to +24.0 deg latitude along the way.

13.0 mega meter distance example
Cabo San Lucas: +22.9 lat -109.9 lon
Manila: +14.6 lat +121.0 long

A straight line path from Cabo has an initial heading of 302.0 deg (32 deg north of west) even though Manila is at a lower latitude (8.3 deg lower.) The great circle path will actually reach up to +38.6 deg latitude along the way.

20 mega meters is halfway around the Earth.

The entire Earth should go Metric

The United States of America is one of 3 countries not using the metric system.

Who enjoys converting miles to feet? Gallons to cups to tablespoons to teaspoons? Tons to pounds to ounces? Speaking of ounces, are you referring to volume or weight? When you say weight, do you really mean mass or weight? In the metric system grams is mass, newtons is force (weight being force due to gravity.)

The word cup can be confusing. Do you mean just a drinking container of an unspecified size, or do you mean 8 ounces?

At least the meter is based on the measurement of the Earth and not some random person's foot! Halfway around the Earth is 20 mega-meters. Even the British abandoned the British system for the French! Feet, miles are in-congruent. Who wants to memorize 5280 in a statute mile? Then you got your 6075 feet per nautical mile to pile onto that. There are 1000 millimeters in 1 meter, there are 1000 meters in 1 kilometer, very simple.

Sure app and search engines will convert, but when you got oil on your hands when cooking do you really want to play with an app on the phone to know how to convert tablespoons to teaspoons? (maybe ask a voice assistant, but if it's loud it probably won't understand you) With metric it's easy to deal with with conversions in your head. 1000ml in a liter, 1000g in a kg, for example. I don't want to remember how many cups in a gallon!

Also the entire Earth should go full metric, km/h isn't much better than mph. You still gotta deal with that unwieldy 3600 second value. Meters per second would be ideal. Say you're travelling at 10 meters/sec (22.3mph) and you have to travel 10 kilometers. Simply divide 10,000 by 10 = 1000 seconds (16.7 minutes). Say you were going 36km/h, how long will it take to travel 10 kilometers? Not readily apparent, gotta do something like 10/36 to get hours, then times that by 60 to get minutes. We should just get rid of hours and minutes and stick with seconds and kilo-seconds to make it even simpler, 86.4 kilo seconds per day.

Related links
http://kilosecond.info/

A better explanation of lift of an airfoil

-Air never leaves the flat bottom, hence it always gets pushed upward, known as lift.
-Drag is air pushing upon the leading edge, bending around it.
-The key is the lack of air on top to apply down pressure.

The reason is that the airfoil traveling above a certain speed causes the following:
-After being displaced by the leading edge air doesn't travel back down to the top surface faster than the top surface tapers downward. Therefore it is unable to apply pressure. It's that simple.

I've heard explanations saying low pressure on top due to higher velocity that is due to farther distance to travel. While those conditions might be true, that does not properly explain the phenomenon.

Airfoils depend on air pressure, going through unpressurized air wouldn't yield any lift (if you could somehow get unpressurized air to stay put that is.)

Precision and accuracy

So many people don't understand that these are fundamentally different aspects.

-Precision is basically how many significant digits, or how many digits right of the radix point.
-Accuracy is how close the measurement is to a target value.

For example:

Dale's discus throw was measured PRECISELY at 36.821 meters.
Bob's discus throw was measured at around 50 meters, plus or minus 2 meters.

Since the target was 50 meters Bob's throw was more ACCURATE than Dales.