Which of the following is true of productivity?
a. the most effective way to continually increase productivity is to work harder. b. more productive workers tend to earn higher incomes.
c. an increase in human capital can increase productivity.
d. productivity is measured as the ratio of output per worker per unit of time.
e. b, c, and d are all correct.

the lowest among the social higher rank were the working class. this class remained detached to the political progression   of the country and was hostile to the other two classes

ww1 weapons: tank. tanks were used for the first time in the first world war at the battle of the somme. they were developed to cope with the conditions on the western front. the first tank was called 'little willie' and needed a crew of 3.

the answer is a) high entry costs

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