How will a decision tree perform on this data set (for the two-class problem)? What if there are four classes?

A 20th century date is assumed when a two digit year between ________ is entered in a worksheet cell

A) 10 and 79 B) 30 and 99 C) 20 and 89 D) 00 and 69

(Stroustrup, Design and Evolution of C++, page 411ff) In each of a) through i), which variable is a local variable? Which statement makes names from a namespace available? (What namespace?) Which are an error? (If so, why?) Which introduce a variable from a namespace? (What namespace?) Which hide a global variable?

What will be an ideal response? ``` #include namespace X { int i, j , k; } int k; void f1() { int i = 0; using namespace X; //a) i++; //b) j++; //c) k++; //d) ::k++; //e) X::k++; //f) using X::i; //g) using X::k; //h) using std::cout; //i) } ```