A corporate venture firm invests in m tech startups across two funding tiers. A Tier-1 startup receives an equity investment of $70,000, and a Tier-2 startup receives $40,000. The total capital invested across all m startups is $1,380,000. The number of Tier-1 startups, t_1, and Tier-2 startups, t_2, are positive integers satisfying t_1 + t_2 = m. If t_1 < t_2 and the product t_1 · t_2 is a square of an integer