The melting point of ice in Fahrenheit scale is........

In the final answer of the expression $\frac{(29.2 - 20.2)(1.79 \times 10^5)}{1.37}$,the number of significant figures is

If an object weighs $275 \ lb$,what is its weight in $kg$? $(1 \ kg = 2.205 \ lb)$

Name the different systems of measurement used.

Which one of the following is not a unit of pressure?

The diameter of a zinc atom is $2.6 \, \mathring{A}$. Calculate $(a)$ the radius of the zinc atom in $pm$ and $(b)$ the number of atoms present in a length of $1.6 \, cm$ if the zinc atoms are arranged side by side lengthwise.