plis tolong di jawab

catatan : * artinya derajat
<B1 = <B2 ; <C3 = <C4 ; <A = 79* ; <B = 60*
a. <C3 + <C4 = 65* + 65* = 130*
b. <B2 = 60* ÷ 2 = 30*
c. <D = 180* - 65* - 80* = 35*

a.∠C3 = ∠A = 70
∠C4 = 40
70 + 40 = 110

b.30 hasil pembagian dua 60

c.∠D = ∠B1 = 30