It seems that you have missed the necessary options for us to answer this question, but anyway here is the answer. William adds two values, following the rules for using significant figures in computations. He should write the sum of these two numbers by using the same number of decimal places as the least precise value. Hope this helps.
Answer is: the energy of exactly one photon of this light is 4.75·10⁻¹⁹ J.
Photon energy equation: E = h·ν.
E - energy of one photon.
ν- frequency.
h - Planck's constant.
ν = 7.17·10¹⁴ Hz.
h = 6.63·10⁻³⁴ J·s.
E = 6.63·10⁻³⁴ J·s · 7.17·10¹⁴ Hz.
E = 4.75·10⁻¹⁹ J.
Answer:
I would say the purple one!
Explanation:
Transporting metals, ions, water-insoluble molecules, and hormones. .... When erythrocytes are removed from circulation,