Which law relates the wavelength of peak emission to the temperature of a body?

1. A hot body radiates across a range of wavelengths. 2. The wavelength that carries the most energy shifts as the body gets hotter. 3. The relation between that wavelength and temperature is Wien's displacement law. 4. The value of the constant is 2.9 times ten to the minus three metre kelvin. _Source: syllabus Physics Part II, Ch 10 'Thermal Properties of Matter'_