I believe it would be B but I'm not 100% sure. Like i warn everyone, TRUST SOMEONE ELSE BEFORE TRUSTING ME. I would hate to see you get the wrong answer cause of me...
Best Hopes,
Cupkake~
<h3>Solution :</h3>
Distance between first tree and last tree is 140m .
And distance between each tree (d) = 5 m
let's solve for number of trees (n) :





hence, total number of trees = 29.
If you flip a coin one time, the probability to get a Head is
p = 1/2
The probability of not getting a head in a single toss is :
q = 1 - 1/2 = 1/2
Thus there is only one unique situation to get the same number of heads and tails : in 10 toss you need to get exactly five heads, it will means that the rest is the tails.
Now using Binomial theorem of probability, the probability of getting exactly x = 5 heads in a total of n = 10 tosses is :
P(X = 5) =
≈ 0.246
So the probability of that is 24,6 %
Good Luck