Physical conditions or diseases that can cause knee pain: 1  osteoarthritis: pain, inflammation, and joint destruction caused by degeneration and deterioration of the joint. 2  tendinitis: pain in the front of the knee that is made worse when climbing, taking stairs, or walking up an incline.
Ages Of US Presidents. John F. Kennedy is the youngest-ever elected president, aged 43. However, Theodore Roosevelt is the youngest person to ever become president. He was 42 when he succeeded to the presidency, following the assassination of McKinley. Ronald Reagan is the oldest person ever to be elected president. He was 69.
Answer: While many mistakenly say that John F. Kennedy was the youngest president of the United States, this is in error. He was the youngest president ever elected to the presidency at the age of 43. However, Theodore Roosevelt was the youngest man to serve as president when he took over after William McKinley's assassination. He was 42. Here are the ages of the ten youngest presidents: 1  Theodore Roosevelt - 42 years, 322 days. 2  John F. Kennedy - 43 years, 426 days. 3  Bill Clinton - 46 years, 154 days.