An object , initially at rest , explodes in three fragments. The momentum of two pieces are −3piˆ and −4pjˆ where p is a positive number. The momentum of the third piece (i) will have magnitude 5p (ii) will make an angle tan^−1(4/3) with the x-axis (iii) will make an angle tan^−1(3/4) with the x-axis (iv) will have magnitude 7p