I am always amazed when I hear people saying that sport creates goodwill between the nations, and that if only the common peoples of the world could meet one another at football or cricket, they would have no inclination to meet on the battlefield.
It is impossible to say simply for the fun and exercise: as soon as the question of prestige arises, as soon as you feel that you and some larger unit will be disgraced if you lose, the most savage combative instincts are around.
It has been found that certain bats emit squeaks and by receiving the echoes, they can locate and steer clear of obstacles——or locate flying insects on which they feed. This echo-本地 in bats is often compared with radar, the principle of which is similar.
As the time and cost of making a clip drop to a few days and a few hundred dollars, engineers may soon be free to let their imaginations soar without being penalized by expensive failure.