What is stroke volume? what happens to it in the physically fit person? what happens to it in the person who isn't physically fit?

What is difference between an epidemic and a pandemic? a) an epidemic is a disease; a pandemic is a treatment.b) an epidemic is restricted to a local region; a pandemic is global.c) an epidemic has low mortality; a pandemic has higher mortality.d) an epidemic is caused by a bacterial infection; a pandemic is caused by a viral infection.