Answer
$-452.11^{\circ}F$
$-268.95^{\circ}C$
Work Step by Step
Use the formula $(Kelvin - 273.15) \times\frac{9}{5}+32$ to convert from Kelvin to Fahrenheit and to convert from Kelvin to Celsius, simply subtract 273.15 from the Kelvin temperature.
$(4.2 Kelvin - 273.15) \times\frac{9}{5}+32 = -452.11^{\circ}F$
$(4.2 Kelvin- 273.15)=-268.95^{\circ}C$