Step-by-step explanation:
Using dimensional analysis, let convert km to cm.
[tex] \frac{4cm}{1km} \times \frac{km}{100000 \: cm} [/tex]
Cancel out the km
[tex] \frac{4cm}{100000 \: cm} [/tex]
[tex] \frac{1}{25000 } [/tex]
So n= 25000
iii.
Dimensional Analysis
[tex] \frac{3 \: cm}{1 } \times \frac{km}{100000 \: cm} [/tex]
[tex] \frac{3 \: km}{100000} [/tex]
Or
[tex]0.00003 \: km[/tex]