Which of the following blood cells differentiate outside of the bone marrow?
A. Neutrophils
Basophils
C. Eosinophils
D. T lymphocytes
E. Megakaryocytes
Which cell type has cytoplasmic granules that contain heparin and histamine?
A. Eosinophils
Basophils
C. Lymphocytes
D. Monocytes
E. Neutrophils
What is the approximate life span of a circulating erythrocyte?
A. 8 days
B. 20 days
C. 5 weeks
D. 4 months
E. 1 year
在以横轴表示生产要素X,纵轴表示生产要素Y的坐标系中,等成本曲线的斜率等于2,这表明( )。
A. Px/Py=2
B. Qx/Qy=2
C. Py/Px=2
D. 上述都不正确
微信支付 
支付宝支付