Company	Microsoft Corp. ($000)	Facebook Inc. ($000)	Tesla Inc. ($000)
Ordinary Shares	900	700	500
10% Debentures	300	200	100
Total Capital	1,200	900	600

The return on capital employed was 15% for each firm in 2019, and in 2020 it was 8%. Corporation tax in both years was assumed to be 40%, and debenture interest is an allowable expense against corporation tax.

(a) Calculate the percentage return on the shareholders' capital for each company for 2019 and 2020. Assume that all profits are distributed. 

(b) Discuss the impact of gearing on the financial stability of these companies.