Verified answer

v = 2*10²⁰

c = 3*10⁸ м/с

[tex]\lambda = ?[/tex]

[tex]\lambda = \dfrac{c}{v} [/tex]

[tex]\lambda = \dfrac{3 \times 10 {}^{8} }{2 \times 10 {}^{20} } = 1.5 \times 10 {}^{ - 12} [/tex]

Ответ: λ = 1,5*10^-12 м