please solve this problem using R language

3. The local corporation authorities in a certain city install 10,000 electric lamps in the streets of the city with the assumption that the life of lamps is normally distributed. If these lamps have an average life of 1,000 burning hours with a standard deviation of 200 hours, then write down the R code to calculate the number of lamps might be expected to fail in the first 800 burning hours and also the number of lamps might be expected to fail between 800 and 1,200 burning hours