Please show work

Pfender Guitars has a current annual cash dividend policy of $7.00. The price of the stock is set to yield a return of 7%. What is the price of this stock if the dividend will be paid a. for 8 years and then the comapny repurchases the stock for $30 ? b. for 12 years and then the comapny repurchases the stock for $30 ? c. for 50 years and then the comapny repurchases the stock for $30 ? d. for 60 years and then the comapny repurchases the stock for $30 ? e. for 100 years and then the comapny repurchases the stock for $30 ? f. forever with no repurchase of the stock