What I think they are trying to say has to do with impulse, or force over time. In the case of a crash, your body is traveling with the car at some speed when the car hits something and stops. The longer it takes for your body to slow down to rest, the less force is applied to your body to slow it down. I believe they are trying to say that currently the force exerted on a person during a crash at 5mph would be the same force as a crash at 28mph in a car that utilizes metal foam.

Did a good job with this. It makes me want to go back and watch the whole Cosmos series. I think they are all on hulu.

Correct, but if there is a large amount of uranium (perhaps in huge fill pools of coal ash etc.), there is likely to be some radon present. Its probably not a big deal though unless the radon is concentrated. All in all you are right because there probably wouldn't be enough spent fuel to create dangerous amounts, I was just commenting.

Don't forget that U234 decays into Rn222 which is where this lovely gas comes from. Given enough uranium, the concentration of radon will build up to deadly amounts.

Is destroying a police robot wrong? Of course besides mere destruction of property? Who is to say people would even listen to a robot? What powers of enforcements would these robots have over humans? I certainly hope they only thing they could do would be spit out citations. This is just the first step in the short story of human extinction by the hands of robots. Nice knowing everyone.