Suppose we want to compute the greatest common divisor of two 1000-digit numbers on a very fast computer—a computer that can do 1 billion divisions per second. Approximately how long would it take to...

Suppose we want to compute the greatest common divisor of two 1000-digit numbers on a very fast computer—a computer that can do 1 billion divisions per second. Approximately how long would it take to compute the gcd by the trial division method? (Choose an appropriate unit of time, such as minutes, hours, days, years, centuries, or millennia.)