Restriction enzymes at a specific sequence
There 2 ways to solve this
1- Directly :
80% of water in the fresh berries è 20% of water in the dried berries
36 Ibs of the fresh berries è X Ibs of the dried berries
X = 
<span> = 9 Ibs</span>
<span>2- </span>If you do not understand the first method, the second one is more explicit:
First, we gonna calculate the weight of the berries without water (dehydrated):
<span>36 * 80% = 28.8 Ibs (of water in the berries)</span>
Then:
<span>36 – 28.8 = 7.2 Ibs (of completely dehydrated berries)</span>
Next, we gonna add 20% of water in the dehydrated berries:
X (total weight of dried berries) è 100%
7.2 Ibs of dehydrated berries è 80%
X = <span> </span>
= 9 Ibs
Answer:
The best explanation was provided by the student Tara who said: "Through photosynthesis, the CO2 and water are changed into new substance, glucose, therefore it is considered a chemical change".
Explanation:
A chemical change is one which is not easily reversible and which results in the formation of new subsatances.
For example, in photosynthesis,a new substance, glucose is formed from the original substansubstances, carbon dioxide and water. Also, the reverse process of the formation of carbon dioxide and water from glucose is not easily obtained in plants.
From explanations provided by the students :
Luke does not give any explanation of the process but only an observation
Jackie's explanation does not state the main reason why a chemical change differs from a physical one.
Tara, gives the best explanation as the reason why a change that occcured is a chemical change is clearly stated.
Skyler does not state the main reason why photosynthesismis a chemical change as well, because even physical changes like evaporation of water involves solar energy.
