What is the correct electron dot formula for a molecule of chlorine

0.66y = 0.9x + 0.48 if y has a value of 108.45 what is the value of x?

Iknow #2 is d. i just need to know why

Acalorimeter is to be calibrated: 51.203 g of water at 55.2 degree c is added to a calorimeter containing 49.783 g of water at 23.5c. after stirring and waiting for the system to equilibrate, the final temperature reached is 37.6 degree c. specific heat capacity of water (s = 4.18 j/g∙degree c). calculate the calorimeter constant. (smδt)warm water = -[(smδt)cold water + (calorimeterδtcold water)]