How to get following answers right using equations and calculator (no excel)

On its 2011 income statement, Richardson Inc. reported net income of $1,420 and on its 2012 income statement, the company reported net income of $1,750. Based on this information (and given the company's balance sheets for 2011 and 2012 in the chart above), compute Net Cash Flows from Investing Activities for Richardson in 2012. Record your answer as a dollar rounded (if necessary) to the nearest whole dollar, but do not include a dollar sign or any commas in your answer. Also, if your answer is a negative value, place a hyphen (i.e., -) before your answer with no space between the - and the number. For example, record -$23,426.9234 as -23427. On its 2011 income statement, Richardson Inc. reported net income of $1,420 and on its 2012 income statement, the company reported net income of $1,750. Based on this information (and given the company's balance sheets for 2011 and 2012 in the chart above), compute Net Cash Flows from Investing Activities for Richardson in 2012. Record your answer as a dollar rounded (if necessary) to the nearest whole dollar, but do not include a dollar sign or any commas in your answer. Also, if your answer is a negative value, place a hyphen (i.e., -) before your answer with no space between the - and the number. For example, record -$23,426.9234 as -23427