I mark as brainliest

D

Step-by-step explanation:

Its d Reason is if she has 5 and he has 10 he has twice as much

Firstly , we can draw diagram

we are given that

XYZ is equilateral triangle

so,

XY=YZ=XZ=6

and when we draw a line from X intersect at mid point between Y and Z

It will also be perpendicular line

so, we can use Pythagoras theorem

now, we can solve for h

so,

..............Answer