Question 1112641
The sketch below shows the situation.
Known lengths, in m, are included along with other labels.
{{{drawing(300,400,-2,10,-1.5,14.5,
triangle(-1,0,-1,1.5,0,0),rectangle(-1,0,-0.8,0.2),
green(triangle(0,0,9,0,9,13.5)), 
blue(arc(0,0,0.6,0.3,0,360)),locate(-0.5,-0.2,blue(puddle)),
green(rectangle(9,0,8.7,0.3)),line(-2,0,11,0),
green(line(9,0,9,13.5)),locate(9.03,9,green(tree)),
locate(-1.6,2.2,Johnna),locate(-2,0.9,1.5),
locate(-0.65,0.6,1),locate(4,0.6,green(9))
)}}} There are two right triangles.
The angles of those triangles at the puddle are the same,
because that is how reflection works.
That makes the two right triangles similar.
The two right triangles have the same shape, but the larger, green triangle
is a scaled up version of the other one.
 
MENTAL MATH SOLUTION:
The scale-up factor is {{{9/1=9}}} ,
so the three is 9 times taller than Johnna,
at {{{9*1.5m=highlight(13.5m)}}} .
 
SHOW-YOUR-WORK SOLUTION:
AS the triangles are similar, their sides are proportional,
so the tree height, {{{green(h)}}} , in m, satisfies
{{{green(h)/9=1.5/1}}} or {{{green(h)/1.5=9/1}}} .
Then, {{{green(h)=9*1.5=highlight(13.5)}}} .