The wall of the heart<span> consists of three </span>layers<span>: the epicardium (external </span>layer<span>), the myocardium (middle </span>layer<span>) and the endocardium (inner </span>layer<span>). The epicardium is the thin, transparent </span>outer layer<span> of the wall and is composed of delicate connective tissue.
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I believe the answer is b.
A Boundary Is A Line That Marks A Limit Of Space. So If You Live In A Neighborhood, Then There Would Be Fences, And That Would Be A Boundary line. It Marks Space And Divides Space. Hope That Helps.
