lambda=(3 times 10^4 mathrm(~m) / mathrm(s))/(9.87 times 10^7) mathrm(~Hz)=

λ = (3 x 10⁴ m/s) / (9.87 x 10⁷ Hz) λ ≈ 3.04 x 10⁻⁴ mTherefore, λ ≈ 3.04 x 10⁻⁴ meters or 304 micrometers.