The length and breadth of a metal sheet are $3.124\,m$ and $3.002\,m$. The area of the sheet is: (in $,m^2$)

The number of significant figures in $0.03240$ is

$A$ student measuring the diameter of a pencil of circular cross-section with the help of a vernier scale records the following four readings: $5.50\, mm, 5.55\, mm, 5.45\, mm, 5.65\, mm$. The average of these four readings is $5.5375\, mm$ and the standard deviation of the data is $0.07395\, mm$. The average diameter of the pencil should therefore be recorded as:

$A$ cube has a side of length $1.2 \times 10^{-2} \; m$. Calculate its volume.

Match the numbers in Column-$I$ with the number of significant figures in Column-$II$.

Column-$I$	Column-$II$
$(1)$ $2.85 \times 10^{26} \ kg$	$(a)$ $1$
$(2)$ $0.009 \ m^2$	$(b)$ $2$
$(3)$ $0.060 \ s$	$(c)$ $3$

Time periods of oscillation of the same simple pendulum measured using four different measuring clocks were recorded as $4.62 \,s, 4.632 \,s, 4.6 \,s$ and $4.64 \,s$. The arithmetic mean of these readings in correct significant figures is: (in $\,s$)