Jamel is asked to create triangles using three of four given sticks. the sticks measure 3 in., 6 in., 7 in., and 8 in. he creates these 4 triangles.
triangle 1: 3 in., 6 in., 7 in.
triangle 2: 3 in., 6 in., 8 in.
triangle 3: 3 in., 7 in., 8 in.
triangle 4: 6 in., 7 in., 8 in.

how many of his triangles are obtuse?
(a.)1
(b.)2
(c.)3
(d.) 4