15% of $300 is (15/100)*$300 = $<<(15/100)*300=45>>45
Emma will earn an annual ROI of $45 for 2 years for a total of $45*2 = $<<45*2=90>>90
10% of $500 is (10/100)*$500 = $<<(10/100)*500=50>>50
Briana will earn an annual ROI of $50 for 2 years for a total of $50*2 = $<<50*2=100>>100
The difference between their ROI after 2 years is $100-$90 = $<<100-90=10>>10
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