You're not going to get 40 miles with a pair of rabbit ears in the living room.
I feel a "Duh" here is appropriate, but maybe you got confused and thought you were posting on a non-tech user forum. My problem is the large hills/small mountains (whatever you want to call them) in between me and the transmitters. TV Fools says I would need a 350 ft tower to get any signal (and even then most things would be 1Edge). And that's not exactly practical in a built up residential area (not sure if it would even be legal, either... if it fell over, it would be more than long enough to hit a neighbor's house).
As to the freesat thing, in the US there are hundreds of local broadcasters who get to run their own local programming and overlay ads.
Yeah, so cut out the middle man. Seems like a good business move to me. It might take some time and some planning, but they can schedule it so all the affiliate contracts expire at the same time and turn it on then.
And one that does 40 mpg will use half the fuel of one that does 20. Yeah, totally unintuitive.
Yes. But that's not the whole story. 40 will use half that 20 does. 20 will use half that 10 does. But 40mpg is 5.88 L/100km, 20 is 11.76 L/100km, 10 is 23.52 L/100km. So switching from a 10 mpg car to a 20 mpg car saves 11.76 L/100km, but switching from a 20 to a 40 mpg car only saves 5.88 L/100km. So that is why mpg is said to be exponential. This is not just me blowing smoke, see https://www.fueleconomy.gov/fe... and look at the section "Fuel Consumption Rate". Even the US department of Energy says Volume/Distance is a better representation (even though they stick to gallons and miles).