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.
century - a period of 100 years. period, period of time, time period - an amount of time; a time period of 30 years; hastened the period of time of his recovery; Picasso's blue period. millennium, millenary - a span of 1000 years.