because transistor is not too hot while vacuum tubes are very easily to get hot
You had better travel near the speed of light or you will not see much of the universe. Unfortunately travelling near the speed is not yet possible, so you are out of luck.
The moon is opaque. Light cannot travel through it.
Yes.
Some, but not all. Some materials are insulators- heat does not travel well through them.
Radiations from the sun are able to travel through space because of the heat waves.
a car idiots!
The invention of the Portuguese ship, the caravel, made travel across the open tropical ocean and against the wind possible in 1492.
yes, they can travel.
Yes of course it is possible to do so.
No. Technically it is not possible.
There is currently no know and confirmed way to travel in time.
No, they do not go that deep
wheels
plane
The Greek invention that aided navel travel and that was improved upon by the Muslims was Greek fire.
Techincally, it is possible, but only because we haven't proven it impossible, either.
To go from one continent to another, humans had to travel by foot or by horse. Unless, of course, there was water in between. The invention of ships made it possible to go between continents.