The answer of the first question is double fertilization !!! I don't get the second question so.... comment if you have that question !!!
In this cross the trait of long tail fins is associated with the “Y” chromosome of the male.
Thus the alleles of the male are represented by XY” where X chromosome has no trait of long tails find
And the allels of the female are represented by XX, as they do not have long tail fins.
When these two are crossed , the following punnet square is produced
X Y”
X X X X Y”
X X X X Y”
The XX is the female while the XY” is the male offspring.
A. off a surface at the same angle it strikes the surface
No it is not as it lacks internal cell membranes.