a)
2, 4, 6, 8, *10
The fifth row contains 10 cans.
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b)
2+4+6+8+10+12+14+16+18+20=110
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c)
2*Row=Number Of Cans
When Row=1, Number Of Cans=2.
When Row=5, Number Of Cans=10.
When Row=10, Number Of Cans=20.