Zero error of an instrument introduces

If the error in the measurement of radius of a sphere is $2\%$ then the error in the determination of volume of the sphere will be ........ $\%$

A physical quantity $y$ is represented by the formula $y=m^{2}\, r^{-4}\, g^{x}\,l^{-\frac{3}{2}}$. If the percentage error found in $y, m, r, l$ and $g$ are $18,1,0.5,4$ and $p$ respectively, then find the value of $x$ and $p$.

The measured value of the length of a simple pendulum is $20 \mathrm{~cm}$ with $2 \mathrm{~mm}$ accuracy. The time for $50$ oscillations was measured to be $40$ seconds with $1$ second resolution. From these measurements, the accuracy in the measurement of acceleration due to gravity is $\mathrm{N} \%$. The value of $\mathrm{N}$ is:

Calculate the mean $\%$ error in five observation

$80.0,80.5,81.0,81.5,82$

$Assertion$ : When percentage errors in the measurement of mass and velocity are $1\%$ and $2\%$ respectively, the percentage error in $K.E.$ is $5\%$.

$Reason$ : $\frac{{\Delta E}}{E} = \frac{{\Delta m}}{m} + \frac{{2\Delta v}}{v}$