$1.5$

$1.5^2=2.25$, so the surface area increases with 125% in two days.

yes, with growth rate $1.5$ until the entire surface is covered.

After $1$ year € 4440 and after $2$ years € 4928,40.

$1.11$

Multiply by $1.11$.

Divide by $1.11$.

$\frac{(7279.45)}{(6740.23)}\approx 1.08$, so the growth rate is $1.08$ and the percentage of growth is 8%.

$N\left(t\right)=5000\cdot 0.{96}^t$

$N\left(10\right)\approx 3324$

$N\left(17\right)\approx 2498$, so after $17$ years.

Calculate the ratios of each two concecutive numbers. You find approximately $1.042$.

4.2% per year.

After $10$ years.

$K\left(5\right)\approx 19254.15$ and $K\left(10\right)\approx 23425.61$

It makes no difference.

School $1$ with a growth rate of $0.95$, so 5% decay.

Linearly, $45$ students less per year.

No, school $2$ will have $0$ students in the end and in school $1$ the number of students decreases slower and slower.

The number of students only changes incidentally during a year. There is a structural change of the number at the beginning of the school year only, depending on the applications and the exam results.