Physics
Radio telescopes are better than optical telescopes because

they can work during the day and night
All of these
they can work even in cloudy conditions
they can detect faint galaxies which no optical telescope can

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Physics
It takes much longer to cook food in the hills than in the plains, because

in the hills the atmospheric density is low and therefore a lot of heat is lost to the atmosphere
n the hills the atmospheric pressure is lower than that in the plains and therefore water boils at a temperature lower than 100oC causing an increase in cooking time
in the hills the humidity is high and therefore a lot of heat is absorbed by the atmosphere leaving very little heat for cooking
due to low atmospheric pressure on the hills, the water boils at a temperature higher than 100oC and therefore water takes longer to boil

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Physics
Light houses are places with powerful lights to :

Guide and help large crowds at religious gathering during nights
Indicate to the incoming warships, the location of a harbour during night
Guide and warn the ships coming from different directions in the ocean
Guide and resolve traffic jams in crowded metro-cities during nights

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