Explanation:
Non-zero digits are always significant.
Zeros between significant digits are also significant.
Trailing zeros are significant only after a decimal point.
(a) 143,700
First, write in scientific notation.
1.437×10⁵
Now, round to 3 significant figures.
1.44×10⁵
(b) 0.09750
= 9.750×10⁻²
= 9.75×10⁻²
(c) 890,000
= 8.9×10⁵
= 8.90×10⁵
(d) 6,764×10⁴
= 6.764×10⁷
= 6.76×10⁷
(e) 33,987.22
= 3.398722×10⁴
= 3.40×10⁴
(f) -6.5559
= -6.5559×10⁰
= -6.56×10⁰