Hello, instructor. I do not understand the meaning of the sentence that "coefficient of determination measures the fraction of the total variation in the dependent variable that is explained by the independent variable". could you please explain again? Thanks.

12. Trumpit Resorts Company currently has 1.2 million common shares of stock outstanding and the stock has a beta of 2.2. It also has $10 million face value of bonds that have five years remaining to maturity and 8 percent coupon with semi-annual payments, and are priced to yield 13.65 percent. If Trumpit issues up to $2.5 million of new bonds, the bonds will be priced at par and have a yield of 13.65 percent; if it issues bonds beyond $2.5 million, the expected yield on the entire issuance will be 16 percent.。Trumpit has learned that it can issue new common stock at $10 a share. The current risk-free rate of interest is 3 percent and the expected market return is 10 percent. Trumpit’s marginal tax rate is 30 percent. If Trumpit raises $7.5 million of new capital while maintaining the same debt-to-equity ratio, its weighted average cost of capital is closest to: A. 14.5 percent. B. 15.5 percent. C. 16.5 percent. 麻烦老师帮忙讲解一下，谢谢！

另外还是刚才那个问题，想问一下就是算出来的，这一个嗯嗯，基准组合的权重设置。的群众还是前后变化的一个变量？delta

8. The Gearing Company has an after-tax cost of debt capital of 4 percent, a cost of preferred stock of 8 percent, a cost of equity capital of 10 percent, and a weighted average cost of capital of 7 percent. Gearing intends to maintain its current capital structure as it raises additional capital. In making its capital-budgeting decisions for the average-risk project, the relevant cost of capital is: A. 4 percent. B. 7 percent. C. 8 percent. 麻烦老师讲解一下，谢谢！

请老师解释一下，这个权重的计算方法，我非常不理解，为什么可以通过这种方式来计算权重？

Additional information: Equity risk premium, Sweden 4.82 percent Risk-free rate of interest, Sweden 4.25 percent Industry debt-to-equity ratio 0.3 Market value of Kruspa’s debt €900 million Market value of Kruspa’s equity €2.4 billion Kruspa’s equity beta 1.3 Kruspa’s before-tax cost of debt 9.25 percent China credit A2 country risk premium 1.88 percent Corporate tax rate 37.5 percent Interest payments each year Level 13. Using the capital asset pricing model, Kruspa’s cost of equity capital for its typical project is closest to: A. 7.62 percent. B. 10.52 percent. C. 12.40 percent. 请老师帮我讲解一下，我找不到公式Ks=rf+beta(rm-rf)中的rm是哪个？谢谢！

请老师，推导一下这个公式，谢谢。

老师您好，请问在capm模型中，他只投资于无风险资产和市场组合，然后老师上课说在这个模型中的这种投资组合方式，我们是没有获取到超额收益的。 我不理解这个为什么我们没有获取到超额收益，请老师给我解释一下，或者举个例子什么的，谢谢了。

老师您好，我不知道怎么用计算器直接算出b1和b0。麻烦解答一下

老师，这道原版书后题的答案我不是特别明白，因为题干里说了是先付年金，但是答案好像是按照后付年金计算的，想请您再帮忙解答解答，多谢！