Answer:
The mean income is the average income of all households in the country, while the median income divides the total into two groups, those who earn above the median and those who earn below the median (i.e. the median would be middle point.)
If income inequality has increased then the mean income should rise above the median income since it is affected by extremes, e.g. the 10% richest earn 9 times more income than the lower 90%.
Since we are not given the increase in income inequality, we can assign any positive slope to the mean income.