Answer:
t=4.86s
Explanation:
To find the wavelength you use the following formula:

v: speed of sound = 343m/s
f: frequency = 400Hz
λ: wavelength of the sound
By doing λ the subject of the formula and replacing the values of f and v you obtain:

Now, to calculate the time that sound takes to reach the last row you use:

t: time
d: distance to the last row = 1947m

hence, the time is 4.86s
Answer:
the answer is C
Explanation:
gravity forces down not up or sideways.
The most waste is Yucca mtn. in Nevada
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Answer:
Selenium dichloride
Explanation:
Selenium (Se) and Chlorine (Cl) are both elements capable of combining together to form a compound with the chemical formula; SeCl2. Since the chlorine atom is more electronegative than selenium atom, the chlorine pulls more electrons towards itself to form an IONIC bond.
The SeCl2 compound formed is called Selenium dichloride as two atoms of Chlorine are needed to combine with one atom of Selenium to form the compound.
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