Find the sum of first 25 terms of the sequence 5,5.5,5.55,5.555-----------

Question

$(a)\;625\qquad(b)\;\infty\qquad(c)\;\frac{5}{81} [2240-0.1^{24}]\qquad(d)\;\frac{5}{9} [225-0.1^{25}]$