fun with triangles

What is the third angle for the triangle where angle1 = 45° and angle2 = 45°? 45° 60° 90°

If a triangle has an angle of 90 degrees, what is it called? obtuse acute right angled

Sum of 3 angles in a triangle is always? 160° 180° 90°

If a triangle has its sides equal to 5cm, 4cm and 6cm, then find its perimeter. 30cm 45cm 15cm

How many side does a triangle have? 2 4 3