When examining a firm’s ownership structure, it is imperative to examine any super-voting rights by certain classes of shareholders. Which of the following statements concerning these voting rights is TRUE（）
A. Super-voting rights by certain classes of shareholders impair the firm’s ability to raise capital for the future.
B. Firms with a single class of common equity could encourage prospective acquirers to only deal directly with shareholders with the supermajority rights.
C. Firms that combine voting rights with economic rights have historically had more difficulty raising equity to invest in capital improvements.
=2.0m／s，物品在转盘上与轴O的距离R="4.O" m，物品与传送带间的动摩擦因数
=O.25。取g=10m/s2。
至少为多大?