4.15 A study of the lifetime (in hours) for a certain brand of light bulb involved putting 10 light bulbs into operation and observing them for 1000 hours. Eight of the light bulbs failed during that period, and those lifetimes were recorded. The lifetimes of the two light bulbs still functioning after 1000 hours were recorded as 10001. The resulting sample observations were 480 790 10001 350 920 860 570 10001 170 290 Which of the measures of center discussed in this section can be calculated, and what are the values of those measures?