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.
(December 2014) A principal investigator (PI) is the holder of an independent grant administered by a university and the lead researcher for the grant project, usually in the sciences, such as a laboratory study or a clinical trial. The phrase is also often used as a synonym for head of the laboratory or research group leader..