If the De Broglie Wavelength of an Electron Is $2.4 \mu \mathrm { m }$

If the de Broglie wavelength of an electron is $2.4 \mu \mathrm { m }$ , what is the speed of the electron? (melectron $= 9.11 \times 10 ^ { - 31 } \mathrm {~kg} , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s }$ )

A) $8.3 \times 10 ^ { 6 } \mathrm {~m} / \mathrm { s }$
B) $2.5 \times 10 ^ { 5 } \mathrm {~m} / \mathrm { s }$
C) $1.7 \times 10 ^ { 3 } \mathrm {~m} / \mathrm { s }$
D) $3.0 \times 10 ^ { 2 } \mathrm {~m} / \mathrm { s }$