Answer:
It is a little bit trivial:
As we know:
Energy sink: is anything that uses energy.
Energy source: is anything that produces energy.
How the caol deposits can be energy sinks? well, you want to extract the coal from those deposits, and to do it, you need to "use energy" (the type of energy can depend on the extraction method, for example, if you use a pickaxe to extract the coal, you are using mechanical energy)
These coals are potential energy sources because coal is an energy source, potential means that, given some circumstances, something can transform into other things.
So potential energy source in this situation means that those coal deposits can be potential energy when we extract the coal and use it as an energy source.
Answer:
Final answer is
.
Step-by-step explanation:
Given expression is 
Now we need to find about what is product of both factors.
We see that both factors are in exponent form having equal base "x".
So we can apply formula: 





Hence final answer is
.
Answer:
t=

Step-by-step explanation:
Multiply both sides by 5/(-6).
*
=
*9
ik the doesnt rlly make any sense but hope this helps
175 mL at 25% concentration of alcohol contains 0.25 (175 mL) = 43.75 mL of alcohol. If <em>v</em> is the amount of the 70% solution that you use, then that amount contains 0.7<em>v</em> mL of alcohol.
Mixing these two yields a total volume of 175 mL + <em>v</em>, and it contains 43.75 mL + 0.7<em>v</em> alcohol. You want to end up with a concentration of 45%, which means the ratio of the amount of alcohol to the total volume needs to be 0.45:
(43.75 mL + 0.7<em>v</em>) / (175 mL + <em>v</em>) = 0.45
Solve for <em>v</em> :
43.75 mL + 0.7<em>v</em> = 0.45 (175 mL + <em>v</em>)
43.75 mL + 0.7<em>v</em> = 78.75 mL + 0.45<em>v</em>
0.25<em>v</em> = 35 mL
<em>v</em> = 140 mL
Answer:
None. Wanda's work is correct.
Step-by-step explanation:
The first is correct.