The period of oscillation of a simple pendulum in an experiment is recorded as $2.63\, s, 2.56\, s, 2.42\, s, 2.71\, s$,and $2.80\, s$ respectively. The average absolute error is ......... $s$.

To estimate $g$ from $g=4 \pi^2 \frac{L}{T^2}$,the error in the measurement of $L$ is $\pm 2 \%$ and the error in the measurement of $T$ is $\pm 3 \%$. The error in the estimated $g$ will be

$Assertion$ : When percentage errors in the measurement of mass and velocity are $1\%$ and $2\%$ respectively,the percentage error in $K.E.$ is $5\%$.
$Reason$ : $\frac{{\Delta E}}{E} = \frac{{\Delta m}}{m} + \frac{{2\Delta v}}{v}$

The density of a solid metal sphere is determined by measuring its mass and its diameter. The maximum error in the density of the sphere is $\left(\frac{x}{100}\right) \%$. If the relative errors in measuring the mass and the diameter are $6.0 \%$ and $1.5 \%$ respectively,the value of $x$ is

$A$ cylindrical wire of mass $(0.4 \pm 0.01) \, g$ has length $(8 \pm 0.04) \, cm$ and radius $(6 \pm 0.03) \, mm$. The maximum error in its density will be $...... \, \%$.

$A$ physical quantity $P$ is related to four observations $a, b, c$ and $d$ as follows: $P = \frac{a^3 b^2}{c \sqrt{d}}$. The percentage errors of measurement in $a, b, c$ and $d$ are $1 \%, 3 \%, 2 \%$ and $4 \%$ respectively. The percentage error in the quantity $P$ is: (in $\%$)