I think the answer is
A) an acid
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Answer:
Calcium is an element With an atomic number of 20. The most common atoms of calcium have a mass number of 40. But some Atoms of calcium have a mass number of 44
What is meant but the tears atomic number
7.5 × 10¹⁹ Electrons flow through a point in a wire in 3.00 s if there is a constant current of i=4.00a.
Q = I × t------------Equation 1
Where Q = charge flowing through the wire, I = current, t = time
Given: I = 4.00 A, t = 3.00 s
Substitute these values into equation 1
Q = 4.00× 3.00
Q = 12.00 C.
But,
1 electron contains 1.6×10⁻¹⁹ C
therefore,
12.00 C = 12.00/1.6×10⁻¹⁹ electrons
= 7.5 × 10¹⁹ Electrons
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Half-life can be given as the time required by the substance to reduce to half of its original concentration. The original mass of Uranium was 11.2 grams.
<h3>What is the expression of half-life?</h3>
The half-life for the reaction can be expressed as;

Where the final mass of the product is, 
The time for the reduction is given as, 
The half-life of the compound is given as, 
The original concentration (
) of the Uranium is given as,

The original mass of uranium-232 has been 11.2 grams.
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