Stresses exerted by brain tumors on neighboring normal brain tissue can cause serious complications. to estimate these stresses, consider a simple model for a growing brain tumor. bars constrained between the rigid sides of the skull represent the tumor (elastic modulus e1) and the brain (elastic modulus e2). at time t = 0, the lengths of the tumor and brain are l1 and l2, respectively, and the bars have equal cross-sectional areas a. l1 skull tumor brain skull l2 (a) suppose tumor growth is represented by a thermal strain t . in terms of t , compute the stress in the brain due to the growing tumor. (b) for a given t , what is the length of the tumor? (c) assume t = a(1 − exp(− where t is time and a and b are constants, and consider the following parameter values: