= Solution
For initial capital zero and a predictable strategy $H$, let $C_t^{0,H}$ denote consumption after the time-$t$ portfolio payoff and before choosing the next holdings. An <investment-consumption arbitrage> has
$$
C_t^{0,H}\geq0\quad\text{for every }t,
$$
with strictly positive consumption at some date with positive probability. A <terminal-consumption arbitrage> is a finite-horizon such strategy whose consumption is zero before its terminal date $T$, while $C_T^{0,H}\geq0$ almost surely and $\mathbb P(C_T^{0,H}>0)>0$.
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