Below is a faulty program that includes a test case that results in failure. Answer the following questions about each program.

/** Count negative elements *

@param x array to search *

@return count of negative elements in x *

@throws NULLPointerException if x is null */

public int countNegative (int[] x) {

int count = 0;

for (int i=x.length-1; i>=0; i++) {

if (x[i] <=0)

count++;

}

return count;

}

// test: x = [-4, 2, 0, 2]; Expected = 1

a. Identify the fault and fix the fault.

b. If possible, identify a test case that does not execute the fault.

c. If possible, identify a test case that executes the fault, but does not result in an error state.

d. If possible identify a test case that results in an error, but not a failure.

e. For the given test case, identify the first error state. Be sure to describe the complete state.