Concept:
For experimental measurements:
If
\[
Z=AB,
\]
then
\[
\frac{\Delta Z}{Z}
=
\frac{\Delta A}{A}
+
\frac{\Delta B}{B}.
\]
Similarly, if
\[
Z=\frac{A}{B},
\]
then
\[
\frac{\Delta Z}{Z}
=
\frac{\Delta A}{A}
+
\frac{\Delta B}{B}.
\]
Relative errors are always added irrespective of multiplication or division.
Step 1: Analyze Statement-I.
For multiplication,
\[
Z=AB.
\]
Therefore,
\[
\frac{\Delta Z}{Z}
=
\frac{\Delta A}{A}
+
\frac{\Delta B}{B}.
\]
Hence Statement-I is correct.
Step 2: Analyze Statement-II.
For division,
\[
Z=\frac{A}{B}.
\]
Relative errors are still added:
\[
\frac{\Delta Z}{Z}
=
\frac{\Delta A}{A}
+
\frac{\Delta B}{B}.
\]
They are not subtracted.
Hence Statement-II is incorrect.
Step 3: Select the correct option.
\[
\boxed{\text{Statement I is correct but Statement II is not correct.}}
\]