need help with these 3 problems

QUESTION 3 Early Corporation issued perpetual preferred stock with a dividend rate of 8.2%, on a par value of $84. The stock currently yields 10%. What is the stock's current market value? QUESTION 4 Holt Enterprises recently paid a dividend, Do. of $2.6. It expects to have nonconstant growth of 19.7% for 4 years followed by a constant rate of 4.6% thereafter. The firm's require return is 15.9%. How far away is the horizon date? QUESTION 5 Maxwell Mining Company's ore reserves are being depleted, so its sales are falling. Also, because its pit is getting deeper each year, its costs are rising. As a result, the company's earnings and dividends are declining at the constant rate of 2.51% per year, if Maxwell's most recent dividend (Do) is $4.57, and its cost of capital is 19.5%, what is the value of Maxwell Mining's stock