This is an inclusive term for several conditions involving inflammation of the kidney. Nephritis is the most common cause of blood in the urine of children and young adults but it can occur at any age. If your GP suspects nephritis he will usually refer you to a nephrologist (kidney doctor).
Quick Answer. The average U.S. car weighs in at just 4,000 pounds, which is two tons. This is the average of all mass manufactured vehicles in the United States.
Today's versions of those cars weigh more like 2700 - 2900 lbs. Something like a hybrid Civic would be at the top end of that scale, if not even heavier. Current mid-size cars, like a Chevy Malibu or Toyota Camry, tend to fall in the 2800 - 3300 lb range, some getting even higher.