Districts of Nepal — Nepal currently comprises 77 districts, which are its second-level administrative country subdivisions.
Answer:
Though the first actual helicopter wasn’t built until the 1940s, it is believed that Leonardo da Vinci’s sketches from the late fifteenth century were the predecessor to the modern day flying machine. As with many of da Vinci’s ideas, he never actually built and tested it – but his notes and drawings mapped out exactly how the device would operate.
Explanation: