A sum of $₹5000$ is invested at $6\%$ per annum simple interest. Calculate the interest at the end of each year and show that they form an $\mathrm{AP}$. Also, find the interest at the end of the ${25}^{\text{th }}$ year.

Find the sum of the following AP:

$40, 36, 32, 28,.....$ to $15$ terms

Find the sum of the following AP:

$3, 8, 13, 18,.....$ to $12$ terms

Find the sum of the following AP:

$-2, -\frac{3}{2}. -1, -\frac{1}{2},.....$ to $25$ terms

Find the sum of the following AP:

$4.5, 4.3, 4.1, 3.9, .....$ to $14$ terms

Find the sum of all terms of the following finite AP:

$63, 61, 59, ....., 35$

Find the sum of all terms of the following finite AP:

$2, 5, 8, ....., 182$

Find the sum of all terms of the following finite AP:

$-10, -2, 6, 14, ....., 78$