Answer:
<u><em>y=7 </em></u><u>number of hours at grocery store</u>
<u><em>x=18 </em></u><u>number of hours at baby- sitting</u>
Step-by-step explanation:
According to the information provided.
x is number of hours at baby- sitting
y is number of hours at grocery store
total number of hours worked
<em>1) </em><em>x+y =25</em>
total earn in a week
<em>2) </em><em>x*$6 + y* $9 = $171</em>
<em />
<em>from equation 1</em>
x+y=25
x= 25-y
<em>we place the above derived equation in equation 2 </em>
x*$6 + y* $9 = $171
(25-y)*$6 + y* $9 = $171
(25*6) -6y +9y =171
150+3y=171
3y=171-150
3y=21
<u><em>y=7 </em></u><u>number of hours at grocery store</u>
x= 25-y
x= 25-7
<u><em>x=18 </em></u><u>number of hours at baby- sitting</u>
Answer:
5%
Step-by-step explanation:
15/300 = 0.05
5%
Electron transfer theory describes the parameters which control the rate at which an electron is transferred from one atom or molecule to another.
<h3>
What was the basic principle of Marcus theory?</h3>
- In theoretical chemistry, Marcus theory is a theory originally developed by Rudolph A. Marcus, starting in 1956, to explain the rates of electron transfer reactions – the rate at which an electron can move or jump from one chemical species.
- Marcus' method (also referred to as Marcus's method and Method of Marcus) is a structural analysis method which was designed to design concrete slabs with rectangular, orthogonal shapes. It represents an adaptation of the strip method.
- Marcus Hush theory (M-H theory) was developed in 1956 by Rudolph A. Marcus which explains the fundamentals of the redox/ electron transfer reactions in terms of the rate of jumping/moving an electron from oxidant species (electron donor) to the reductant (electron acceptor).
- The "Marcus Inverted Region" (MIR) is that part of the function of rate constant versus free energy where a chemical reaction becomes slower as it becomes more exothermic.
We want to see how we can model the difference: -8 - 3 + 3
The correct option is D:
"add 3 positive counters and 3 negative counters"
We know that Marcus starts with 8 negative counters, corresponding to the first term in our difference.
Now, let's study the math of our expression.
-8 - 3 + 3
Remember that we can perform the operation in any order we want, so we can write this as:
-8 + (-3 + 3)
Notice that the thing inside the parentheses is equal to zero, so we have:
- 8 + (-3 + 3) = -8
So to not change the value, we add 3 and we subtract 3.
Now if we have 8 negative counters, and we want to add 3 positive counters and not change the value, then we also need to add 3 negative counters to "cancel" the 3 positive counters we added.
Then the correct option is D.
To learn more about Marcus refer to,
brainly.com/question/23140234
#SPJ1
To find how many miles per hour, we divide the number of miles hiked by the number of hours it took to hike them.
=15.12 miles ÷ 6.3 hours
=2.4 miles hiked per hour
Hope this helps! :)
