Accuracy of measurement is determined by

Explain Absolute Error,Relative Error,and Percentage Error.

The temperature of a body measured by a thermometer with a least count of $0.2 ^\circ C$ is $37.8 ^\circ C$. The temperature with error is represented as ... and the percentage error of the observation is ...

$A$ wire has a mass $0.3 \pm 0.003 \text{ g}$,radius $0.5 \pm 0.005 \text{ mm}$ and length $6 \pm 0.06 \text{ cm}$. The maximum percentage error in the measurement of its density is (in $\%$)

The International Avogadro Coordination project created the world's most perfect sphere using Silicon in its crystalline form. The diameter of the sphere is $9.4 \,cm$ with an uncertainty of $0.2 \,nm$. The atoms in the crystals are packed in cubes of side $a$. The side is measured with a relative error of $2 \times 10^{-9}$,and each cube has $8$ atoms in it. Then,the relative error in the mass of the sphere is closest to (assume molar mass of Silicon and Avogadro's number to be known precisely)

If the absolute error is $0.05 \ m$ for a measured length of $5 \ m$, what is the percentage error (in $\%$)?