What is the Certified Pool/Spa OperatorÂ® Certification Program? A CPOÂ® Certification provides individuals with the basic knowledge, techniques, and skills of pool and spa operations. This training has helped protect millions of swimmers by reducing hazards at aquatic facilities.
A year is the orbital period of the Earth moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by changes in weather, the hours of daylight, and, consequently, vegetation and soil fertility.
decade (s) (noun) , decades (pl). 1. A period of ten years; especially, one beginning with a year that ends in a 0, for example 2000 through 2999: One hundred years is equal to ten decades and one decade is equal to ten years..ecade (s) (noun) , decades (pl). 1. A period of ten years; especially, one beginning with a year that ends in a 0, for example 2000 through 2999: One hundred years is equal to ten decades and one decade is equal to ten years..