A nurse is caring for a postoperative patient who is at high risk for deep vein thrombosis (DVT) due to immobility. The patient is currently on bed rest with the left leg elevated and has been advised to perform specific exercises to promote circulation. The nurse instructs the patient to perform leg raised straight exercises. Each time the patient raises the left leg, it is noted that the patient can only lift it to an angle of ____ degrees. Considering the significance of maintaining optimal mobility to prevent complications like DVT, identify the angle of elevation that indicates a fair level of mobility.