The error in the measurement of length and mass of a cube is $3\%$ and $4\%$ respectively. The error in the measurement of its density will be (in $\%$)

$A$ quantity $Q$ is formulated as $Q = X^{-2} Y^{\frac{3}{2}} Z^{-\frac{2}{5}}$. $X, Y$ and $Z$ are independent parameters which have fractional errors of $0.1, 0.2$ and $0.5$,respectively,in measurement. The maximum fractional error of $Q$ is:

If $x = 10.0 \pm 0.1$ and $y = 10.0 \pm 0.1$,then $2x - 2y$ is equal to

We measure the period of oscillation of a simple pendulum. In successive measurements,the readings turn out to be $2.63 \;s, 2.56 \;s, 2.42 \;s, 2.71 \;s$,and $2.80 \;s$. Calculate the absolute errors,relative error,and percentage error.

$A$ current of $(2.5 \pm 0.05) \ A$ flows through a wire and develops a potential difference of $(10 \pm 0.1) \ V$. The resistance of the wire in $\Omega$ is:

In an experiment for determination of the focal length of a thin convex lens,the distance of the object from the lens is $10 \pm 0.1 \text{ cm}$ and the distance of its real image from the lens is $20 \pm 0.2 \text{ cm}$. The error in the determination of focal length of the lens is $n \%$. The value of $n$ is. . . . . . .