All elements in a period have the same energy level due to which of the following reasons

In a good thermo flask the main cause of heat loss is

Apatient has a history of poor nutrition. he has skin rashes, bleeding gums, and a cut that hasn’t healed in a long time. what vitamin deficiency most likely caused this symptom?

On your wedding day your lover gives you a gold ring of mass 3.67 g. 48 years later its mass is 3.44 g. on the average how many atoms were abrated from the ring during each second of your marriage? the atomic mass of gold is 197 u. don't enter units