СРОЧНО!!!!!
[tex] \lim_{n \to \infty} (7/10+29/100+...+(2^n+5^n)/10^n)[/tex]

summ (2^n + 5^n)/10^n = summ (2^n/10^n) +summ (5^n/10^n)= summ (1/5^n) +summ (1/2^n)= 1/5*1/(1-1/5) +1/2*1/(1-1/2) == 1/4 +1= 1,25