Hot oil is cooled from 80 to 50°C in an oil cooler which

Hot oil is cooled from 80 to 50°C in an oil cooler which uses air as the coolant. The air temperature rises from 30 to 40°C. The designer uses a LMTD value of 26°C. The type of heat exchanger is

θ₁ = 50° , θ₂ = 10°
θ₁ = 40° , θ₂ = 20°
As given value is between these two, so cross flow is the best option.