units_time1 http://www.openmath.org/cd/units_time1.ocd 2006-08-27 experimental 2004-08-27 1 0 This CD defines symbols to represent the basic physical units of time in the SI (syst\'eme international) system of units. and therefore most other modern systems such as "Imperial" and "U.S.". second This symbol represents the measure of one second of time. This is the standard SI unit measure for time. This is a base unit for the SI system minute This symbol represents the measure of one minute of time. 1 minute = 60 seconds 1 60 hour This symbol represents the measure of one hour of time. 1 hour = 60 minutes 1 60 day This symbol represents the measure of one day of time. The definitions below ignore the possibilities of "leap seconds". 1 day = 24 hours 1 24 week This symbol represents the measure of one week of time. 1 week = 7 days 1 7 calendar_month This symbol represents the measure of one month of (calendar) time. 1 month = 28..31 days 28 31 calendar_year This symbol represents the measure of one year of (calendar) time. 1 year = 365..366 days 365 366 1 year = 12 months 1 12