doubt in kathy sierra question?

[Hennry Smith]

1. class Comp2 {
2. public static void main(String[] args) {
3. float f1 = 2.3f;
4. float[][] f2 = {{42.0f}, {1.7f, 2.3f}, {2.6f, 2.7f}};
5. float[] f3 = {2.7f};
6. Long x = 42L;
7. // insert code here
8. System.out.println("true");
9. }
10. }
And the following five code fragments:

F1. if(f1 == f2)
F2. if(f1 == f2[2][1])
F3. if(x == f2[0][0])
F4. if(f1 == f2[1,1])
F5. if(f3 == f2[2])

What is true?
A. One of them will compile, only one will be true
B. Two of them will compile, only one will be true
C. Two of them will compile, two will be true
D. Three of them will compile, only one will be true
E. Three of them will compile, exactly two will be true
F. Three of them will compile, exactly three will be true

Actual answer:
Answer:
D is correct. Fragments F2, F3, and F5 will compile, and only F3 is true.

A, B, C, E, and F are incorrect. F1 is incorrect because you can’t compare a primitive to
an array. F4 is incorrect syntax to access an element of a two-dimensional array.

please explain each of this in detail....i am confused in array...

[Mohamed Sanaulla]

I would suggest you have a look at the Array Tutorials.

f2- Is an Array of Arrays of float values. So f2[0] would actually return an Array float values. f2[0][0] would actually return an float value.
f3- Its just an array of float values.