Main.cc: In function 'int main()': Main.cc:9:5: error: 'filter' was not declared in this scope filter b; ^ Main.cc:12:9: error: 'b' was not declared in this scope b=6; ^ Main.cc:16:9: error: 'b' was not declared in this scope b=6+(a-2)*0.5; ^ Main.cc:19:9: error: 'b' was not declared in this scope b=6+(10-2)*1.8+(a-10)*1.8*1.5; ^ Main.cc:21:11: error: 'b' was not declared in this scope cout<