// Equivalent Diameter

function EquivalentDiameter(a, b){
	this.a = a; 
	this.b = b;
}

EquivalentDiameter.prototype.equivalentDiameter = function(){
	var d = 1.30*Math.pow((this.a * this.b),0.625)/Math.pow((this.a + this.b),0.25);
	return d;
}

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