Which of these shapes is not a quadriateral

A triangle is not a quadrilateral since a quadrilateral is a shape with four sides and a triangle has three sides

A triangle because it doesn't have 4 sides

Answer light in color; silica-rich;

Your answer is d. silli hope this ! : ) i left an explanation down below if you need it: a sill forms when hot magma squeezes between layers of rock to form a hardened sheet of rock. a sill is basically a tabular sheet intrusion between old layers of sedimentary rock, volcanic beds, or in the direction of foliation inherent in metamorphic rock. the word sill means a concordant intrusive sheet.