男性，18岁，午后发热盗汗2个月，左胸痛伴胸闷3周。B超、X线胸片发现左侧中等量胸腔

患者，女，18岁，冠折1/2，咬合关系正常，患牙经根管治疗后，最好选用哪种桩冠修复（）

A.成品桩桩冠

B.金属核桩冠

C.铸造舌背桩冠

D.纤维桩桩冠

E.1.2mm不锈钢丝弯制桩冠

下列排列顺序正确的是                                  （  ）

A热稳定性：H₂O＞HF＞H₂S    B.原子半径：Na＞Mg＞O   C.酸性：H₃PO₄＞H₂SO₄＞HClO₄

Helmut Humm, manager at a large U. S. firm, has just been assigned to the capital budgeting area to replace a person who left suddenly. One of Humm’s first tasks is to calculate the company’s weighted average cost of capital (WACC). Humm finds clear notes on the target capital component weights. Unfortunately, all he can find for the cost of capital components is some handwritten notes. He can make out the numbers, but not the corresponding capital component. So, he has to guess. Here is what Humm deciphered: Target weights : w_d = 30% , w_ps = 20% , w_ce= 50% , where w_d, w_ps, and w_ce are the weights used for debt, preferred stock, and common equity. Cost of components (in no particular order) : 6.0% , 15.0% , and 8.5%.The cost of debt is the after-tax cost. If Hummguesses correctly, the WACC is:（）

A. 9.2%.

B. 11.0%.

C. 9.0%.

在计算机中，算法是指 ______。

A．查询方法

B．加工方法

C．解题方案的准确而完整的描述

D．排序方法