The following questions are accompanied by three statements (I), (II), and (III). You have to determine which statements(s) is/are sufficient/necessary to answer the questions.

Find the amount of money invested by Jamnalal in the scheme? 

I. An increase in simple interest from 44/3% to 58/3% per annum increases his yearly income by 2800.

II. The sum invested get doubled, when invested at 20% per annum for 5 years.

III. Amount on sum is twice in 5 years.