The floating platform shown is supported at each corner by a hollow sealed cylinder 1 m in diameter. The platform itself weights 30 kN in air, and each cylinder weighs 1.0 kN per meter of length. What total cylinder length L is required for the platform to float 1 m above the water surface? Assume that the specific weight of the water (brackish) is 10,000 N/m^3. The platform is square in plan view.