Answer:
50 years.
Step-by-step explanation:
Rule 70 is used in finance to roughly determine the time required to double the investment. The calculation is made by dividing 70 by the percentage of interest in the period. In this case, we use the annual growth rate, 1.4, thus; 70: 1.4 = 50. This figure shows that Brazil's GDP will be doubled, maintaining growth of 1.4% per year over 50 years.