Many doctors believe this decline in hormone levels triggers the symptoms of PMS. Changes in brain chemicals or deficiencies in certain vitamins and minerals may also play a role. Too many salty foods, alcohol, or caffeine may make symptoms worse as well.
There have been countless flights made since the invention of the airplane by the Wright Brothers in 1903. It should come as no surprise that the first commercial flight in history occurred in the United States. In fact, it occurred on January 1, 1914, three years before the United States entered the first World War.
They Taught the World to Fly! Wind, sand, and a dream of flight brought Wilbur and Orville Wright to Kitty Hawk, North Carolina where, after four years of scientific experimentation, they achieved the first successful airplane flights on December 17, 1903. With courage and perseverance, these self-taught engineers relied on teamwork and application of the scientific process.