Answer:
Step-by-step explanation:
Subset of A = { {} , {a} , {b}, {a.b} }
The function is:
B ( t ) = 4 * e^(0.8 t)
4 * e^(0.8 t) = 400
e^(0.8 t) = 400: 4
e^(0.8 t) = 100 / ln
ln e^(0.8 t) = ln 100 ( and since: ln e = 1 and ln e^x = x * ln e )
0.8 t = 4.6
t = 4.6 : 0.8 = 5.76 ≈ 6
Answer:
D ) 6 hours.
Answer: Choice C and Choice D
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Explanation:
- Choice A doesn't work because it the $1 should be $7 instead.
- Choice B doesn't work because it should be Elena spending $7 total on 3 notebooks and a $1 pen. The x is the amount per notebook.
- Choice C does work. If x is the number of grapes Noah gives each friend, then 3x is the total amount Noah gives over. Then 3x+1 is the number of grapes total. That +1 at the end is the grape Noah eats. We end up with 3x+1 = 7 because Noah starts off with 7 grapes.
- Choice D works also. The x is the number of hours for math, science and history each. So 3x is the combined time of those three classes. Add on 1 to get 3x+1 to represent all 7 hours, ie 3x+1 = 7.
- Choice E does not work. If it was her spending $7 on 3 markers and a $1 pen, then it would work.
Answer:
The reactant that acts as an acid, by contributing an H⁺ ion to create H3O+ in the chemical equation is C₆H₅OH.
Step-by-step explanation:
According to Brønstend-Lowry, an acid is a substance that transfer a proton (hydrogen cation, H⁺) to a base, forming a base conjugate for the first and an acid conjugate for the second.
From the following reaction:
C₆H₅OH(aq) + H₂O(l) → C₆H₅O⁻(aq) + H₃O⁺(aq)
We have that the C₆H₅OH transfer a proton to the water to form its conjugate base C₆H₅O⁻ and the conjugate acid of water H₃O⁺. Hence, the C₆H₅OH is the acid and the water is the base.
Therefore, the reactant that acts as an acid, by contributing an H⁺ ion to create H3O+ in the chemical equation is C₆H₅OH.
I hope it helps you!
