a) 11:51 − 10:00 =
[R]

b) 6:10 − 4:14 =
[R]

c) 10:28 − 8:09 =
[R]

d) 7:34 − 5:09 =
[R]

e) 11:33 − 10:16 =
[R]

f) 9:05 − 7:33 =
[R]

g) 10:09 − 8:13 =
[R]

h) 10:13 − 6:21 =
[R]

i) 10:09 − 8:28 =
[R]

j) 8:02 − 5:33 =
[R]