strictly speaking, profits are the net earnings in a period as a result of doing business. In order for a company to do its business, it usually needs to invest upfront prior to conducting business, let's say before the first period of consideration, which is usually considered period 0. Sometimes companies amortize the investment costs over a number of periods and consider the amortisation a fixed cost. Most often investment costs are not included in the fixed costs. In such a case, I suggest splitting the financial branch of your structure into two segments (profits (t>=1) and investment (t=0)). That's a safe and MECE way. If in doubt, ask the interviewer which approach (s)he prefers.
Best of luck,