Answer:
5,41%
Step-by-step explanation:
Remark
It's hard to interpret what % increase means. I'm going to work first with the actual increase and then I'll give the % increase. The answer I give will likely be in your choices, but it could still be incorrect.
Givens
Walking distance from A to B = 10 units down + 10 units east + 10 units down + 10 units east + 10 units down + 10 units east = 60 units.
Swimming distance = 2*sqrt(10^2 + 30^2) = 63.25 units.
Solution
The difference = 63.25 - 60 = 3.25
The % increase = (3.25/60)*100 = 5.41%