A jet fighter is flying at 1200 m- elevation above your head as shown in figure. It is moving with Mach .number of 1.8 1200m The distance (X) that the observer :will hear the aircraft is اخترأحد الخيارات a. X=1300.6 meters b. X-1550.4 meters c. None of these d. X-1910.8 meters

Please show written work

Eratosthenes of Cyrene [born ca. 276 BCE, Cyrene, Libya-died ca. 194 BCE, Alexandria, Egypt] made the first measurement of the size of Earth for which any details are known. His method is illustrated. On the first day of summer he observed that the sun was directly overhead at noon in Cyrene. At the same time the sun was 7.2° from overhead in Alexandria, which is distance d north of Cyrene. From the data, estimate the radius of Earth, in miles. [Data for Alexandria Syene d = 787 km] from Sun

1. In the operation of an internal combustion engine, the combustion gases expand in volume to make the piston move. As this occurs piston. Select the most correct phrase to go into this blank from these choices: gas particles move in the same direction as the motion of the A all the В almost all of the very few of the about half of the