Table:
quantities of dried cannabis

mean
95% confidence interval

lower limit
upper limit

total grams

average
27.5
22.7
32.3

gender

males
27.6
21.3
33.9

females
27.6
20.6
34.6

age group

15 to 24
18.9
10.7
27.0

25 or older
30.0
24.5
35.6

cannabis product type

dried (flower/leaf) only
22.1
15.9
28.4

dried (flower/leaf) other
33.7
26.5
41.0

frequency of use

daily or almost daily
62.6
52.3
72.9

weekly
12.0
8.9
15.1

monthly
8.3
3.7
12.8

once or twice
2.6
1.5
3.7

Based on this table picture, can you identify any merged cells and give their coordinates in the JSON format {'top-left':(X1, Y1), 'bottom-right':(X2, Y2)}, where (X1, Y1) and (X2, Y2) correspond to the top-left and bottom-right (row_id, column_id) of the merged area? The row_id and column_id should start from 1 rather than 0.

The merged cell regions are as follows:
{'top-left':(1, 1), 'bottom-right':(3, 1)}
{'top-left':(1, 2), 'bottom-right':(1, 4)}
{'top-left':(2, 2), 'bottom-right':(3, 2)}
{'top-left':(2, 3), 'bottom-right':(2, 4)}
{'top-left':(4, 2), 'bottom-right':(4, 4)}
{'top-left':(6, 2), 'bottom-right':(6, 4)}
{'top-left':(9, 2), 'bottom-right':(9, 4)}
{'top-left':(12, 2), 'bottom-right':(12, 4)}
{'top-left':(15, 2), 'bottom-right':(15, 4)}.