a) 6:45 − 4:12 =
[R]

b) 12:15 − 8:26 =
[R]

c) 9:48 − 6:11 =
[R]

d) 8:50 − 5:09 =
[R]

e) 8:37 − 6:03 =
[R]

f) 11:23 − 8:15 =
[R]

g) 4:24 − 2:12 =
[R]

h) 7:47 − 6:12 =
[R]

i) 4:18 − 2:37 =
[R]

j) 12:04 − 10:44 =
[R]