$A\left(10\right)=25000\cdot 1.1^{10}\approx 64844$

$A\left(10\frac{7}{12}\right)\approx 68551$

$1.1$

$1.1^{\left(\frac{1}{12}\right)}\approx 1.008$ so approximately 0.8% per month.

$A(-5)\approx 15523$ and $A(-10)\approx 9639$

Check that $A(-5)\cdot 1.1^{(-5)}=A(-10)$.

1-1-2001: € 7518.15
1-1-2000: € 7092.60
1-1-1999: € 6691.13

On $1$ January 1996.

He deposited € 5000 on $1$ January 1994.

$g_{\left(\text{3 hours}\right)}=\frac{3000}{1200}=2.5$

$g_{\left(\text{1 hour}\right)}={(2.5)}^{\left(\frac{1}{3}\right)}\approx 1.357$ so 35.7% per hour.

$H\left(t\right)=1200\cdot 1.{357}^t$

Around two and a quarter hours before $t=0$.

See table

See table