This question can likely be answered using the formula E=hc/w where w is wavelength, h is Planck's constant, c is the speed of light, and E is energy in Joules. 5 electrons are emitted when calcium is flashed with light of wavelength 340 nm and intensity of 50 percent.
Remove the hog-rings as you roll the cover up over the seat. If your seat has a hard back, there will be a series of screws along the bottom that hold the bottom of the hard back to the seat. Unscrew these, and then pull open the hard back slightly to determine if the hardback needs to be slid up or down to be removed.
When possible, use a reciprocating saw with a demolition blade to cut nails between the bottom plate and the stud bottom. This frees the stud, which you can pry free from the nails above. If you don't have room to wrangle an 8-foot stud, cut the stud in the middle and then pry out each half. Plates.