They are about 4.5 billion years old. Hope this helps.
When sulfur reacts with zinc metal is forms a compound known as zinc sulfide.
<h3>
Name of the elements</h3>
The names of the elements that make up the compound will be determined from the atomic mass of the elements.
<h3>Which element has atomic number 30</h3>
The element that atomic number of 30 is zinc and it has oxidation number of +2.
<h3>Which element has atomic number 16</h3>
The element that atomic number of 16 is sulfur and it has oxidation number of -2.
<h3>Chemical reaction between sulfur and zinc metal</h3>
Zn²⁺ + S²⁻ --------> ZnS
Thus, when sulfur reacts with zinc metal is forms a compound known as zinc sulfide.
Learn more about zinc sulfide here: brainly.com/question/20806552
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A) -0.5(9.8)*t^2 = -25(t-2) - 0.5(9.8)(t-2)^2
-4.9t^2 = -25t + 50 - 4.9(t^2-4t+4)
0 = -25t+50+19.6t - 19.6
5.4t = 30.4
t = 5.62962963 s
b) h = -4.9(5.62962963)^2
h = -155.2943759
the building is 155.2943759 m high
c) speed 0of first stone
= at
= 9.8*5.62962963
= 55.17037037 m/s
speed of second stone
= v + at
= 25+9.8*3.62962963
= 60.57037037 m/s