Explanation:
m<5 = 60 (<5 & 60deg < are vertical)
m<6 = 120 (<s 5 and 6 are a linear pair)
m<9 = 120 (<s 6 and 9 are vertical)
m<4 = 80 (<s 4 and 80 deg < are vertical)
m<7 = 100 (<7 and 80 deg < are linear pair)
m<10 = 100 (<s 7 and 10 are vertical <s)
m<8 = 60 (<s 5 and 8 are corresp <s)
m<3 = 80 (80 deg <3 are corresp <s)
m<2 = 40 (80 + 60 + m<2 = 180)
m<1 = 60 (<s 1 & 5 are alt int <s)