A问:如果living expense在last year 是300,000 USD, current year 的expense按老师讲的,已经含在了investment portfolio, 《相当于 300,000 * (1+2.5%)》,求coming year (相当于next year) 的liquidity needs,这里的"next year / coming year"的living expense 为什么不是 300,000 * (1+2.5%)^2,而是300,000 * (1+2.5%)?