Learning how to fly took nature millions of years of trial and errorbut a winged robot has cracked it in only a few hours, using the same evolutionary principles. To begin with, the robot just twitched and jerked erratically. But, gradually, it made movements that gained height. At first , it cheated simply standing on its wing tips was one early short cut. After three hours, however, the robot abandoned such methods in favor of a more effective flapping technique, where it rotated its wings through 90 degrees and raised them before twisting them back to the horizontal and pushing down. The robot had metre-long wings made from balsa wood and covered with a light plastic film. Small motors on the robot let it move its wings forwards or backwards, up or down or twist them in either direction. A computer program fed the robot random instructions, at the rate of 20 per second, to test its flapping abilities. Each instruction told the robot either to do nothing or to move the wings slightly in the various directions. 1.Which of the following is NOT true of what is mentioned about the winged robot in the second paragraph? B. The two professors of CUT tested whether the winged robot could learn to fly. D. The two professors of CUT tried to find out if the robot could fly by itself. A. It rotated its wings through 90 degrees. C. It was twitched and broke down. 3.Which of the following is nearest to Peter Bentleys view on the winged robot? B. The winged robot did not have a mortor. D. The robot could fly if it were lighter. A. Two vertical rods. B. A movement detector. 5.What does the process appearing in the last paragraph refer to? B. Sending instructions to the robot. D. All the above.
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