A 78-year-old man with a history of hypertension presents with progressive exertional dyspnea and occasional chest tightness. On examination, there is a harsh, late-peaking systolic ejection murmur heard best at the right upper sternal border, radiating to the carotids. Transthoracic echocardiography is performed. Which of the following combinations of aortic valve area and mean transvalvular gradient is most consistent with severe aortic stenosis?