I need the vocab definition quick

Which element forms an ionic bond with flourine? 1) fluorine 2) carbon 3) potassium 4) oxygen

What is the ima of the 1 st class lever in the graphic given? 2 3 0.5

In a heat engine of 1000 j of heat enters the system and the piston does 500 j of work what is the final internal energy of the system if the inital energy was 2000 j we have to do all of these down here 1)write the equation 2)list out your know variables 3)plug the numbers into the equations 4)solve 5)write your solution statemtn that includes inital energuy and final energuy added