In the 1870s and the 20th, there were similar changes in wage growth due to technological progress. In the 1870s, this wage growth led to an increase in working hours. In the 20th century, this wage growth led to a decrease in working hours. How can we use the concepts of income and substitution effects to understand why the impact of these otherwise similar changes in wage growth was different in the 1870s compared to the 20th century? You should use a diagram to show these effects in each time period