A water tank consists of a cylindrical part of radius r and height h and a hemispherical top. The tank is to be constructed to hold 600 m³ when filled. The surface area of the cylindrical part is 2πrh, and its volume is πr²h. The surface area of the hemispherical top is given by 2πr², and its volume is given by 2πr³/3. The cost to construct the cylindrical part of the tank is $400 per square meter of surface area; the hemispherical part costs $600 per square meter. Use the fminbnd function to compute the radius that results in the least cost. Compute the corresponding height h.