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Arjun plans to retire on his 65th birthday. However, he plans to work part-time until he turns 72. During these years of part-time work, he will neither make deposits to nor take withdrawals from his retirement account. Arjun will fully retire on his 72nd birthday. Assuming that Arjun can earn 7.8% p.a. on all money invested in his retirement account, what annual amount, starting on his 34th birthday, will Arjun have to save in order to have $2,500,000 in his account on his 72nd birthday