schweser vol 2 - 2pm - 20.4

The question is asking for # of futures contract need to short to hedge the Japanese equities exposure of 162,225,000,000 with the following information: Nikkei futures 10337 Nikkei div yield 1% time to expiration 6 months Japanese risk free rate 2% Multiplier 5 Nikkei futures beta 1 Japanese portfolio beta 0.9 Exchange rate 108.15/ A) 24k ~ 25k contracts B) 25k ~ 26k contracts C) 26k ~ 27k contracts The answer calculated as C). My question is how come it isn’t discounted by risk free rate for 6 months? The first question of this item set #20.1 asking how many futures contract to neutralize the total equity position, answer got multiplied by US risk free rate of 5 months. What’s the difference here? Under what circumstance to consider the risk free rate, and when we don’t need to? Thanks.