What is the approximate energy of a photon having a frequency of 4 × 107 hz? ( h = 6.6 × 10-34 j. s)?

Can someone me with questions 12 and 13 plz.

How do limiting factors most affect population size? ostop population growthrestrict population growthincrease population sizeresult in positive impactso

Which statement is true about the model of the electromagnetic spectrum a: it change the frequencies of light. b: it compare wavelengths of light. c: the color of light waves can be changed using the model. d: the intensities of light waves can be decreased using the model.