How are arteries different from veins and capillaries? Describe the functions of both arteries and veins

Explain the advantage of having a closed circulatory system over an open circulatory system

Why would atherosclerosis result in a heart attack? Provide a brief explanation based on how the heart functions.
How are arteries different from veins and capillaries? Describe the functions of both arteries and veins.
Vertebrates and some invertebrates have a closed circulatory system.
Explain the advantage of having a closed circulatory system over an open circulatory system