Answer:
a. $30,000
Step-by-step explanation:
First we calculate the share of preferred dividend, common shareholders will receive the residual after preferred stock holders have been paid.
Preferred dividend payable = (10,000*100)*0.05 = $50,000
In 2011 no dividend was paid so 50,000 was carried forward to 2012
In 2012 90,000 was paid
Of this $90,000, preferred dividend of 50,000 was paid for 2011 leaving the dividend amount as $40,000.
For 2012, 50,000 was again payable for preferred but only 40,000 of this was paid thus carrying forward $10,000 payable to preferred stock holders.
In 2013, Again 90,000 was declared. Of this 10,000 was paid to preferred for 2012 leaving the dividend amount to 80,000. For 2013 again 50,000 for preferred was payable and after paying this the net amount available for Common stock holders was
=80,000-50,000 = $30,000
Hope that helps.