[tex]\bf \qquad \textit{Simple Interest Earned by Mrs A}\\\\
I = Prt\qquad
\begin{cases}
I=\textit{interest earned}\\
P=\textit{original amount deposited}\to& \$350\\
r=rate\to 4\%\to \frac{4}{100}\to &0.04\\
t=years\to &5
\end{cases}
\\\\\\
I=350\cdot 0.04\cdot 5\implies \boxed{A=70}\\\\
-------------------------------\\\\[/tex]
[tex]\bf \qquad \textit{Simple Interest Earned by Mrs B}\\\\
I = Prt\qquad
\begin{cases}
I=\textit{interest earned}\\
P=\textit{original amount deposited}\to& \$500\\
r=rate\to 3.5\%\to \frac{3.5}{100}\to &0.035\\
t=years\to &5
\end{cases}
\\\\\\
A=500\cdot 0.035\cdot 5\implies \boxed{A=87.5}\\\\
-------------------------------\\\\[/tex]
[tex]\bf \qquad \textit{Simple Interest Earned by Mrs C}\\\\
I = Prt\qquad
\begin{cases}
I=\textit{interest earned}\\
P=\textit{original amount deposited}\to& \$280\\
r=rate\to 4.25\%\to \frac{4.25}{100}\to &0.0425\\
t=years\to &5
\end{cases}
\\\\\\
A=280\cdot 0.0425\cdot 5\implies \boxed{A=59.5}[/tex]
so, notice who made how much, so the order from least(smallest) to greatest(largest) will be C, A, B.
