2) ab5c=36k, k integer
a*10^3+b*10^2+5*10+c=36k
mod 36 gamu....
28*a+28*b+14+c=0 (mod 36)..........XXX
c =(0,2,4,6,8)...c ta hariyanne mechcharai...
ooka hariyana combination 9k thiyanawa.....check karama...
c=2;,
28*a+28*b+2+14=0 (mod 36)
7*a+7*b+4=0 (mod 9)
-2*a+-2*b+4=0 (mod 9)...