>> x = input('Enter something: '); Enter something: x + 6 >> f = input('Enter something: '); Enter something: _________ >> fprintf(f, x) x + 6 = 10 Consider the dialog above with Matlab. What was actually entered for f is not being shown, instead you see underscores. Which of the following statements are true:

1. The hidden entry could be 'x + %d = 10 ', but only if x is initially -2

2. The hidden entry could be 'x + %d = 10 ', but only if x is initially 0

3. The hidden entry could be 'x + 6 = %d ', but only if x is initially 4

4. Entering the x + 6 causes an error