A spider rested on a wall 5 feet from the floor. It starts climbing up the wall 1/2 foot every...

A spider rested on a wall 5 feet from the floor. It starts climbing up the wall 1/2 foot every hour. When it reaches a height of 8 feet, it starts climbing back down, 1/2 foot every hour. How high up the wall will the spider be at the end of 10 hours?