context: The luminous efficiency of a fluorescent lamp is several times greater than that of incandescent lamps of a similar power. The service life of fluorescent lamps is about 5 years, provided that the number of starts is limited to 2000, that is, no more than 5 times a day during the warranty period of 2 years.
question: What is the life span of a modern luminescent lamp?
answers.text: 5 years