Answer:
The right answer minimum number of $5 cetificates that each nephews and nieces will get is 2 and maximum number of $5 certificates that each will get is 4.
Explanation:
The minimum number of $5 certificates that each nephews and nieces will get is 2 because he can add $25 + $10 = $35 , he has now capacity of $20 ($55 - $35) in which he can add one more $10 the he must have to add 2 of $5 certificates.
The Maximum number of $5 certificates he can give is 4 because again when he adds every certificate once he has capacity of $20 ( $55 - $25 - $10). He can now add 4 * $5 = $20 so he can get $55.
Considering the definition of percentage by mass, the sample of pure lithium nitrate contains 7.99% lithium by mass.
<h3>Definition of percentage by mass</h3>
The percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.
In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.
The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:

<h3>This case</h3>
Because percent by mass indicates the ratio of solute to solution based on mass, if the sample has twice the mass of the first sample, the ratio remains constant.
So the percentage by mass is the same.
That is, the sample of pure lithium nitrate contains 7.99% lithium by mass.
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Learn more about percent by mass:
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It is important to calculate discounts independently to ensure that each discount is applied to the price of each product. ... It is also important to calculate them to know the real total price of the purchase you are going to make.
Aerobics exercise are practice or training routines which is aimed at strengthening the muscles and aiding general fitness. Aerobic exercises performed in a water or pool, they are called water aerobics or aquatic fitness routines.
Hence, <em>swimming laps are not a form of aerobics</em>. Hence, the Statememt is false.
Swimming is a sport on its own which is performed inside a pool. Water aerobics however are performed in shallow waters and are meant to improve aquatic fitness. Water aerobic routines include ; <em>Water yoga, Zumba and aqua jog</em>.
Therefore, swimming is not a water aerobic routine.
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