#### Answer

(a) $0.00574~kg$
There are three significant figures in this measurement.
We can write this measurement in scientific notation:
$5.74\times 10^{-3}~kg$
(b) $2~m$
There is one significant figure in this measurement.
We can write this measurement in scientific notation:
$2~m$
(c) $0.450\times 10^{-2}~m$
There are three significant figures in this measurement.
We can write this measurement in scientific notation:
$4.50\times 10^{-3}~m$
(d) $45.0~kg$
There are three significant figures in this measurement.
We can write this measurement in scientific notation:
$4.50\times 10~kg$
(e) $10.09\times 10^4~s$
There are four significant figures in this measurement.
We can write this measurement in scientific notation:
$1.009\times 10^5~s$
(f) $0.09500\times 10^5~mL$
There are four significant figures in this measurement.
We can write this measurement in scientific notation:
$9.500\times 10^3~mL$

#### Work Step by Step

We can find the number of significant figures in each measurement and write each measurement in scientific notation.
(a) $0.00574~kg$
There are three significant figures in this measurement.
We can write this measurement in scientific notation:
$5.74\times 10^{-3}~kg$
(b) $2~m$
There is one significant figure in this measurement.
We can write this measurement in scientific notation:
$2~m$
(c) $0.450\times 10^{-2}~m$
There are three significant figures in this measurement.
We can write this measurement in scientific notation:
$4.50\times 10^{-3}~m$
(d) $45.0~kg$
There are three significant figures in this measurement.
We can write this measurement in scientific notation:
$4.50\times 10~kg$
(e) $10.09\times 10^4~s$
There are four significant figures in this measurement.
We can write this measurement in scientific notation:
$1.009\times 10^5~s$
(f) $0.09500\times 10^5~mL$
There are four significant figures in this measurement.
We can write this measurement in scientific notation:
$9.500\times 10^3~mL$