What is the lowest frequency photon that can ionize a hydrogen atom with excited state electron configuration 4s1?

Which element would mostly likely have an electron affinity measuring closest to zero

If anyone would be able to me out with these three questions it would be these are from the chem 2202 course.

When 13.3 g koh is dissolved in 102.7 g of water in a coffee-cup calorimeter, the temperature rises from 21.4 °c to 31.53 °c. what is the enthalpy change per gram of koh (j/g) dissolved in the water? * take the density of water as 1.00 g/ml. * assume that the solution has a specific heat capacity of 4.18 j/g*k. enter to 1 decimal place. do not forget the appropriate sign /(+). canvas may auto-delete the (+) sign