40. The interatomic distance for a metal is

40. The interatomic distance for a metal is 3×10^-10 m . If the interatomic force constant is 3.6×10^–9 N/Å , then the Young’s modulus in N/m² will be

(a)  1.2×10¹¹                                            (b) 4.2×10¹¹

(c) 10.8×10^-19                                        (d)  2.4×10¹⁰

Answer-a

(9)