这里的cost为什么直接用5而不是PV（5）

问题如下：

Given the spot price of crude oil at $120 per barrel, a risk-free rate of 3% with annual compounding, a futures contract due in 182 days, and storage costs of $5 per barrel payable at contract settlement, what is the closest estimate for the futures price per barrel of crude oil?

选项：

A.$126.78

B.$126.86

C.$126.93

解释：

FP=(S₀+PV₀C)(1+rf)^182/365=S₀ (1+rf)^182/365+FVC=120(1+0.03) ^182/365+5=126.78