spread不乘以2吗
问题如下图：
选项：
A. 
B. 
C. 
解释：
1.15% 1.25% A is correct. The expectetotholng-periocost for investing in the ETF over a nine-month holng periois calculatefollows: Totholng-periocost = Annumanagement fee + Rountrip trang commissions + Bioffer spreon purchase/sale. Totholng-periocost = (9/12) × (0.40%) + 0.55% + 0.20% =1.05%. 哪里体现了买入卖出的整个过程，使得sprea用完整的biask spread
NO.PZ2015121810000067 1.15% 1.25% A is correct. The expectetotholng-periocost for investing in the ETF over a nine-month holng periois calculatefollows: Totholng-periocost = Annumanagement fee + Rountrip trang commissions + Bioffer spreon purchase/sale. Totholng-periocost = (9/12) × (0.40%) + 0.55% + 0.20% =1.05%. 题目中给的是rountrip commission和吧biask sprea问题是持有期的totcost 还没有卖啊，不应该是9/12*0.4%+（0.55%+0.2%）*0.5吗？
如题，不是买入卖出要2遍么？那应该乘以2
