Street Parking: Metered parking available on Charles St. $1.25 per hour; 2 hour maximum before having to move to a different meter. Valet parking: Available starting at 5 PM daily. Valet charge is $20. Garage Parking: Boston Common Parking Garage- Charles St./Beacon St. corner of garage.
By definition, pi is the ratio of the circumference of a circle to its diameter. Pi is always the same number, no matter which circle you use to compute it. For the sake of usefulness people often need to approximate pi.
Polyimide (sometimes abbreviated PI) is a polymer of imide monomers. Polyimides have been in mass production since 1955. With their high heat-resistance, polyimides enjoy diverse applications in roles demanding rugged organic materials, e.g. high temperature fuel cells, displays, and various military roles.