Can error be completely eliminated?

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

Consider a series of measurements of the length of a box in an experiment. The readings are $2.4 \ m, 2.5 \ m, 2.6 \ m, 2.8 \ m, 3.0 \ m$. What would be the relative error?

$A$ particle covers a distance of $(13.8 \pm 0.2) \ m$ in $(4 \pm 0.3) \ s$. Its velocity under error limits will be

The initial and final temperatures of water as recorded by an observer are $(40.6 \pm 0.2)^{\circ}C$ and $(78.9 \pm 0.3)^{\circ}C$. Calculate the rise in temperature with proper error limits.

$A$ packet contains silver powder of mass $20.23 \,g \pm 0.01 \,g$. Some of the powder of mass $5.75 \,g \pm 0.01 \,g$ is taken out from it. The mass of the powder left back is ................