The sixth chapter of mathematics in the next semester of Grade 8 proves that in the unit tests 1 and △ABC, ∠ b = 45 and ∠ c = 72, then an external angle adjacent to ∠A is equal to degrees. 2. In △ABC, ∠ A+∠B=1/kloc-0, ∠ C = 2 ∠ A, then ∠A= degree, ∠ B = degree. 3. If the difference between two acute angles in a right triangle is 20, the sum of the degrees of these two acute angles. 4. Rewrite the following proposition "Equal vertex angles" as: If, then. 5. As shown in the figure, AD and AE are the bisector and height line of △ABC respectively; ∠ B = 50, ∠ C = 70, then ∠EAD= degrees. 6. As shown in the figure, ∠ BDC = 142, ∠ B = 34, ∠ C = 28, then ∠A= degrees. 7. As shown in the figure, it is known that DB bisects ∠ADE, de ∠ AB and ∠ CDE = 82, then ∠EDB= degrees, and A= degrees. 8. As shown in the figure, in △DF⊥ABC, point D is a point on ray BC, DH intersects AB at point H, and AC intersects at point E, then the size relationship between ∠HEC and ∠AHE is: 9. As shown in the figure, △ABC, ∠B=∠C, E is AC, and ED ⊥. If ∠ AED = 140, ∠C= 10, as shown in figure △ABC, BP divided by ∠B, CP divided by ∠C, if ∠ A = 60, ∠BPC= degrees. 1 1, the following statement is propositional () A, have you had lunch? B, the intersection point A is a straight line MN C, the complementary angle of the same angle is equal to D, the face is red 12, and there are () A, ∠B+∠A=∠C B, ∠A:∠B:∞ which are not right triangles. Then the shape of this triangle is () a, acute triangle b, obtuse triangle c, right triangle d, uncertain 14, acute triangle, and the range of maximum angle α is () a, 0.