(3 points) (a) Considering a top down approach to modeling the spread of epidemics, list 3 mathematical techniques which have been used by modelers. (3 points) (b) Considering a bottom up approach to modeling the spread of epidemics, list 3 mathematical techniques which have been used by modelers. (4 points) (c) Consider spread of an epidemic of some infectious disease in some spatially distributed population of individuals, e.g. spread of Covid-19, or flu. List characteristics of such epidemic which a bottom up approach to mathematical modeling allows incorporating more realistically, or more easily, than a top down approach. (3 points) (a) Considering a top down approach to modeling the spread of epidemics, list 3 mathematical techniques which have been used by modelers. (3 points) (b) Considering a bottom up approach to modeling the spread of epidemics, list 3 mathematical techniques which have been used by modelers. (4 points) (c) Consider spread of an epidemic of some infectious disease in some spatially distributed population of individuals, e.g. spread of Covid-19, or flu. List characteristics of such epidemic which a bottom up approach to mathematical modeling allows incorporating more realistically, or more easily, than a top down approach