A total of 100 maintenance costs, C, for ground-mounted transformers in high-density housing areas was collected by the City Electricity Authority. The costs are clustered into $200 cells with midpoints ranging from $600 to $2000. The number of times (frequency) each cell value was observed and its probability are shown. Find the expected value of the costs, E(C), for use in a present worth (PW) analysis. Cell Midpoint, Ci Frequency 600 6 Probability 0.06 800 10 0.10 1000 9 0.09 1200 15 0.15 1400 26 0.26 1600 17 0.17 1800 7 0.07 2000 10 0.10 The expected value of the costs is $