Now answer the following questions: hat type of telephone increased most during the period 1968-1980? 11 How is the overall business productivity calculated? 12 How is telecom manpower productivity calculated? 13 ow is engineering manpower productivity calculated? Now look back at the terms of reference on page 15. Which of the terms of reference do the figures illustrate? a) Fig. 1. b) Fig. 2. c) Fig. 3. d) Table 1. 15 Which of the illustrations would you change to a different format(table graph, graph table) in order to make the points more clearly?