Consider a spherical tumor of radius rT that is covered with capillaries that provide oxygen at a constant concentration CB. There are no capillaries inside the tumor, where oxygen consumption is constant at a rate of 0.a) Define the system and the environment and include a labeled drawing. b) Identify the source (point of highest concentration) and sink (point of lowest concentration) for the mass transfer process. c) Write a molar balance equation for the appropriate chemical species within the system. Identify which terms can be dropped from the equation (i. e. which terms do not apply for the given scenario).d) Identify which types of boundary conditions should be used for the transport situation. there will be two boundary conditions.