Day and night is due to the earth rotating. Seasons are due to the earth rotating on a slightly tilted axis, causing light to be shone on different parts of the earth more directly during different parts of the year. Constellations changing throughout the night are because of the earth moving and rotating. Throughout the year, the earth moves, causing us to be facing different directions in different parts of the year. The North Star does't move because it is close to Earth's line of axis, and therefore does not appear to move.
The salivary amylase did not perform well if the pH becomes lower because it needs neutral pH for performing its functions.
<h3>Effect of pH on the enzyme</h3>
We can say that the salivary amylase did not perform their function very well within the stomach due to unfavourable environment such as lower pH. Due to lower pH, the enzyme structure is damaged so unable to perform its function so we can conclude that the salivary amylase did not perform well if the pH becomes lower.
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Answer:

Explanation:
Alkaline earth metals are in group 2. The number of valence electrons of elements in group 2 is 2.
53.5 g MgCl2 /95.21 g/mol = 0.5619 Moles MgCl2. Since the ratio is 3MgCl : 2Na3PO4 you multiply 0.5619 x 2/3 (since you're solving for NaPO, the 2 goes on top) which shows we have .3746 Moles of NaPO. Multiply times it's molar mass so 0.3746x 163.94g/mol= 61.4136 grams NaPO. I believe.
A toy train <span>has characteristics similar to a scientific model
because its a working model of concept
so correct option from above i conclude is D
hope it helps</span>