Answer:
The unknown radioactive element is present in pitchblende.
Explanation:
Marie Curie was the scientists that mainly worked on the radioactive element. She was the first scientist who won the noble prize in two different fields of science.
The pitchblende was the mineral sample that was noticed by Marie curie during her experiment. Pitchblende contains a more radioactive element that uranium and confirms that she had found a new element.The new element was polonium with hundred times more radioactive than uranium.
Thus, the answer is unknown radioactive element is present in pitchblende.
2. Releases a substance called pathogen to fight the invader.
Answer:
Subliminal perception
Explanation:
Subliminal perception can be defined as the process in which a person triggers someone mind to have a desire for a thing using sensory stimuli that are below such person
threshold for conscious perception and this often happen either through visual or auditory which enables the conscious mind of the person to register it in which it will be audible enough for the person subconscious mind. And in some cases the person may receive information from the senses that he /she is not consciously aware of.
Therefore Dr. Rafael’s experiment demonstrated SUBLIMINAL PERCEPTION
Epithelial tissue covers your body as well as lines your internal organs
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