hello
to solve this question, we need to use the formula of simple interest which is
[tex]\begin{gathered} s.i=p(1+rt) \\ p=\text{ principal} \\ r=\text{rate} \\ t=\text{time} \end{gathered}[/tex]the prinicipal (p) = $9800
rate (r) = 7% = 7 /100 = 0.07
time (t) = 4 years
now let's substitute the values into the formula
[tex]\begin{gathered} s\mathrm{}i=9800(1+0.07\times4) \\ s\mathrm{}i=9800(1+0.28) \\ s\mathrm{}i=9800\times1.28 \\ \text{s}\mathrm{}i=12544 \\ \end{gathered}[/tex]the simple interest on her deposit after 4 years is $12544