1. (8 points) Consider the C program given below. You will be asked to determine which variables are visible in a number of different sit- uations. In each case, identify each variable by its name and the line number of its declaration. 1 int h, i; 2 void B(int w) { 3 int j, k; 4 i = 2*w; 5 w = w+1; 6 ... 7 } 8 void A (int x, int y) { 9 float i, j; 10 B(h); 11 i = 3; 12 ... 13 } 14 void main() { 15 int a, b; 16 h = 5; a = 3; b = 2; 17 A(a, b); 18 B(h); 19 ... 20 } (a) C uses static scoping. Say which identifers (including variables and function names) are visible in the bodies of each of the func- tions: main, A, B. 1 (b) If C used dynamic scoping and the calling sequence is main calls B. Say which identifers would be visible in B. (c) If C used dynamic scoping and the calling sequence is main calls A. Say which identifers would be visible in A. (d) If C used dynamic scoping and the calling sequence is main calls A; A calls B. Say which identifers would be visible in B.

2.During the execution of a Java program, can a variable be visible but not allocated? Can a variable be allocated but not visible? Explain your answers.