Mel Wonders When He Will Be Able to Find Out

question 80

Multiple Choice

Mel wonders when he will be able to find out the sex of his baby. You tell him that he should be able to detect the sex of the fetus with ultrasound by the __________ week of pregnancy.

• A) ninth
• B) twelfth
• C) fifteenth
• D) eighteenth

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Definitions:

Atomic Number

The atomic number of an element is the number of protons in the nucleus of an atom, defining the element and determining its position in the periodic table.

First Energy Level

The initial level of energy that an electron in an atom can have, closest to the nucleus.

Electrons

Negatively charged particles that circle around an atom's nucleus.

Ion

Atom or molecule that carries a net charge.