Suppose that a certain atom possesses only four distinct energy levels. Assuming that all transitions between levels are possible, how many spectral lines will this atom exhibit? 
Definitions:
Endocrine Structure
Refers to any organ or gland in the body that secretes hormones directly into the blood rather than through a duct.
Oviduct
A tube through which an ovum or egg passes from an ovary, also known as the fallopian tube in females.
Corpus Albicans
A regressed form of the corpus luteum, which is a temporary endocrine structure in female ovaries.
Perineum
The region of the body between the anus and the genitals, encompassing the pelvic floor and associated structures.
Q40: Complete the following nuclear equation: <img src="https://d2lvgg3v3hfg70.cloudfront.net/TB4071/.jpg"
Q53: If uranium were to split into three
Q83: Glass is transparent to light of wave
Q93: In what sense can you truthfully say
Q99: A transformer requires<br>A)alternating voltage.<br>B)direct current.<br>C)both<br>D)neither
Q107: What happens if you were to place
Q113: Which of the following elements is a
Q123: What does the following element description actually
Q135: How necessary is soap for removing salt
Q141: What it the main difference between an