Answer: Chemical weathering changes the composition of a rock, while physical weathering does not.
Explanation: The definition of a chemical change is a change that cannot be reversed and is caused by a chemical reaction. In this case, a chemical change to a rock would change the composition of the rock while physical changes may change the appearance of the rock, but not the composition.
The average of the following set of measurements is 20°C.
To find the average of the given set of measurements
Given:
Set of measurements = 27°C, 12°C, 31°C, 19°C, 23°C, 11°C, 17°C
Number of Observations = 7
Average = Sum of observations/Total number of observations
Sum of observations = 27°C+12°C+31°C+19°C+23°C+11°C+17°C
= 140
Total number of observations = 7
Substitute the values in the formula
= 140/7 = 20°C
Therefore, the average of the following set of measurements is 20°C
To learn how to calculate average of a set of measurements, refer
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<span>Sodium pumps and potassium pumps will not be triggered to open or close therefore causing the cell to remain at electrochemical equilibrium (-70 mv) so there will be no movement of ATP. Also the phosphates needed to create ATP will be inhibited and with a negative charge the cell will not reach threshold to propagate a reaction along the axon.</span>
B
Vaccinations protect people when they are exposed to the microorganism to which they were vaccinated. This secondary response happens when the person is exposed to the microorganism. At that time, IgG production is a lot higher, making it the main antibody class in the second response. IgM is more active when it comes to the first exposure. A lot of people who have allergies have IgE in their bodies, too. IgA is the most common secretory antibody, and it stops pathogens from attaching and invading through the mucosal membranes of the body.
