Normal dimensions of the human heart for a live persons can be determined noninvasively using magnetic resonance imaging (MRI) or two dimensional echocardiography (2DE). (S.Kaul, et al., Measurement of normal left heart dimensions using optimally oriented MR images, AM. J. Radiol. 146:75-79, 1986.) During systole the left ventricular cavity has a diameter of about 34 mm and the wall thickness is about 16 mm. If systolic pressure is 130 mmHg, estimate the wall tension assuming that the wall stress is constant and that the ventricle is a sphere of the dimension given. Estimate the wall stress.