We use a standard notation: $a$, $b$, and $c$ denote the sides of the triangles and their lengths, and $A$, $B$, and $C$ denote the angles opposite $a$, $b$, and $c$, respectively, as indicated in the nearby figure.

Thus $a$ and $b$ are the lengths of the two short sides, and $c$ is the hypotenuse. Use the Pythagorean Theorem to compute any missing length. Assume also that $A$ denotes the angle opposite $a$, $B$ the angle opposite $b$, and, of course, $C$ the right angle.
I recommend that in this problem you enter values of the trig functions as fractions.
Suppose $a=5$ and $b = 12$. Then
$c =$ ,
$\sin(A) =$ ,
$\cos(A) =$ , and
$\tan(A) =$ .