Based on your understanding of color's relationship to wavelength, identify the approximate wavelength of light (nm) emitted by strontium when it was burned. Explain your reasoning in full, making sure to cite specific data and observations to support your answer.

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.

the answer is d. 74.02