Hi, would someone pls help me tackel this questio?. Thank you

In a study of 100 firms, a regression of investment on earnings is analyzed, that is,

I i = α + β 1 Е i + u i

Where I is investment and E is earnings for each firm i.

1) Suppose some firms report pre-tax earnings and other firms report post-tax earnings, but this information is unknown to the researcher. What are the implications for the regression estimates of α and β?

2) Suppose the distribution of profits is non-normal across the firms. What are the implications for the regression estimates of α and β?

3) Suppose that a group of firms do not invest at all, that is , I=0. Show that the regression estimates of α and β is biased.

4) Suppose that a group of firms invest all their earnings, that is I=E. What is the effect on the regression estimates of α and β?