[填空题]
In a triangle ABC,AB=12 cm and AC=15 cm. Tbqrm+d3 z3qla q*4x h1he area o z48y:c8m*txvr2s huif the triangle is $80cm^2$.
1.Find the two possible values for angle BÂC. $^{\circ}$, $^{\circ}$
2.Given that BÂC is obtuse, find the length of side BC. cm