积极强化
参考答案：
在积极行为发生后，立即用物的或精神的鼓励来肯定这种行为。在这种作用下，个体感到对他有利，从而增加以后的行为反应频率。
眼角膜手术时，全身麻醉应配合实施
A．表面麻醉
B．脊髓麻醉
C．局部浸润麻醉
D．面神经传导麻醉
E．三叉神经传导麻醉
What is the maximum price an investor should be willing to pay (today) for a 10 year annuity that will generate $ 500 per quarter (such payments to be made at the end of each quarter) , given he wants to earn 12 percent, compounded quarterly（）
A. $11300.
B. $11557.
C. $6440.
