本次美国代写主要为经济学的限时测试
1.在线性规划问题中，最优解的约束条件是：
5×1 + 3×2≤30
2×1 + 5×2≤20
只要目标函数的斜率保持在________和________之间，当前的最佳值
解点将保持最佳状态。
一种。 -5 / 3，-2 / 5
b。 -3 / 5，-5 / 2
C。 -5 / 3，-5 / 2
d。 -3 / 5，-2 / 5
e。两种可能的答案是正确的。
2.线性规划模型的________属性表示变化的速率或斜率。
目标函数或约束是恒定的。
一种。添加剂
b。可除性
C。肯定
d。相称性
e。技术
3.松弛变量：
一种。是≥约束的左侧小于右侧的量。
b。是≤约束的左侧小于右侧的量。
C。是约束左侧和右侧之间的差异。
d。线性规划问题中的每个变量都存在。
e。与双重松弛变量相关联。
F。给出的答案可能不只一个是正确的。
4.对于最大化问题，影子价格衡量的是最优值的________
解决方案，对于给定的________，每单位增加。
一种。减少，输入
b。增加，参数
C。改善，投入
d。减少，参数
e。改进，决策变量
5.假设我们使用0-1整数规划模型来解决资本预算问题和xj
如果选择项目j，则= 1，否则选择xj = 0。约束（x1 + x2 + x3 + x4 = 2）表示
必须从________个项目中选择________个。
一种。恰好1、2
b。恰好2、4
C。至少2、4
d。最多1、2
e。最多1、
1. In a linear programming problem, the binding constraints for the optimal solution are:
5×1 + 3×2 ≤ 30
2×1 + 5×2 ≤ 20
As long as the slope of the objective function stays between ________ and ________, the current optima
solution point will remain optimal.
a. -5/3, -2/5
b. -3/5, -5/2
c. -5/3, -5/2
d. -3/5, -2/5
e. Two of the possible answers are correct.
2. The ________ property of linear programming models indicates that the rate of change or slope of the
objective function or a constraint is constant.
a. additive
b. divisibility
c. certainty
d. proportionality
e. technology
3. A slack variable:
a. is the amount by which the left side of a ≥ constraint is smaller than the right side.
b. is the amount by which the left side of a ≤ constraint is smaller than the right side.
c. is the difference between the left and right side of a constraint.
d. exists for each variable in a linear programming problem.
e. is associated with the dual slack variable.
f. more than one of the possible answers given is correct.
4. For a maximization problem, the shadow price measures the ________ in the value of the optimal
solution, per unit increase for a given ________.
a. decrease, input
b. increase, parameter
c. improvement, input
d. decrease, parameter
e. improvement, decision variable
5. Assume that we are using 0-1 integer programming model to solve a capital budgeting problem and xj
= 1 if project j is selected and xj = 0, otherwise. The constraint (x1 + x2 + x3 + x4 = 2) means that
________ out of the ________ projects must be selected.
a. exactly 1, 2
b. exactly 2, 4
c. at least 2, 4
d. at most 1, 2
e. at most 1, 4