How should you saw a block of stone of 40 kg into four pieces such that you can measure all weights of an integer from 1 kg to 40 kg (so 1 kg, 2 kg, 3 kg, 4 kg, ..... 39 kg and 40 kg) on a balance?

Two men were discussing which one of them owned the best horse. To find out, they decided to organize a match. Because both of the men did not like to loose, they agreed on doing a ride as slow as possible. The last horse which would pass the finish would be the best one. The match started, but of course it did not proceed at all. After several hours the horsemen jumped of their horses and agreed upon something. After this short talk they jumped back on the horses and went with full speed to the finish. What did they agree upon?

A wire with a length of 60 meter is hanging between two high voltage pylons. The wire is connected to the pylons at a height of 50 meters. The middle part of the wire is 20 meters above ground level. How far are the high voltage pylons standing apart?