Answer :
Check below, please.
1) Let's effectuate those multiplications noticing the dot
[tex]0.01\times0.9=\frac{1}{100}\times\frac{9}{10}=\frac{9}{1000}=0.009[/tex]Note that since we have3 zeros on the denominator we'll have 3 decimal places, similarly:
1 b.
[tex]0.9\times0.12=\frac{_{}9}{10}\times\frac{12}{100}=\frac{108}{100}=1.08[/tex]Notice that we can write those decimal numbers as fractions.
2 a.
[tex]0.04\times0.4=\frac{4}{100}\times\frac{4}{10}=\frac{16}{1000}=0.016[/tex]2 b.
[tex]0.7\times0.2=_{}0.14[/tex]3 a.
[tex]0.06\times0.4=\frac{_{}6}{100}\times\frac{4}{10}=\frac{24}{1000}=0.024[/tex]3 b.
[tex]0.1\times1.1=\frac{_{}1}{10}\times\frac{11}{10}=\frac{11}{100}=0.11[/tex]
4 a.
[tex]0.4\times0.11=\frac{_{}4}{10}\times\frac{11}{100}=\frac{44}{1000}=0.044[/tex]
4 b.
[tex]0.07\times0.1=_{}0.007[/tex]
5 a.
[tex]0.7\times1.2=_{}0.84[/tex]
5 b.
[tex]0.2\times0.05=_{}0.01[/tex]