A _________ is a mark of depth about 10 mm to 20 mm which is placed on the face of a brick to form a key for holding the mortar?

A _________ is a mark of depth about 10 mm to 20 mm which is placed on

1.	A _________ is a mark of depth about 10 mm to 20 mm which is placed on the face of a brick to form a key for holding the mortar?
A.	Tooting
B.	Cownose
C.	Frog
D.	Bullnose
Answer» D. Bullnose