Open Question: geometry i need help!!please!!!?

there are two right triangles (picture them)
one right triangle has the bottom a number 3 and the long side a 6
the second right angle has the bottom a number 4 and the long side a 12;

so . Are these triangles similar? If so, state a reason ?

If triangle has two sides measuring 2 and 5 and another triangle has corresponding sides measuring 3 and 7.5 with included angles equal, are these triangles similar? If so, state a reason.
you have to use the figure for those two questions.

If 2 triangles have sides measuring 4-4-6 and 2-2-4, are the triangles similar? If so state a reason.

If the triangles are equilateral, are these triangles similar? If so state a reason.

then a PROOF!!! PLEASE HELP.

Prove all equilateral triangles are similar.

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