Answer:
455 or 680, depending
Step-by-step explanation:
If we assume the three choices are different, then there are ...
15C3 = 15·14·13/(3·2·1) = 35·13 = 455
ways to make the pizza.
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If two or three of the topping choices can be the same, then there are an additional ...
2(15C2) +15C1 = 2·105 +15 = 225
ways to make the pizza, for a total of ...
455 + 225 = 680
different types of pizza.
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There is a factor of 2 attached to the number of choices of 2 toppings, because you can have double anchovies and tomato, or double tomato and anchovies, for example, when your choice of two toppings is anchovies and tomato.
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nCk = n!/(k!(n-k)!)
10/6 = 1 2/3
This is because 5 + 5 =10/6
Divide 19 by six.
This gives you 1 2/3
C. liquid to solid.
When things get cooler, they go from gas to liquid to solid. If you know water is a solid, and you know it's cooling and changing states, then you can correctly infer that it is changing from a liquid to a solid.
The porosity of the gravel sample is 28.75%
We have to determine.
What is the porosity of the gravel sample?
<h3>The porosity of the gravel sample;</h3>
Porosity is the term which is defined as the volume of voids present in the soil to the total volume of the soil.
The formula used to calculate the Porosity is;

A sponge is a case of a permeable fabric because it incorporates a huge number of purge spaces compared to its volume.
Porosity is the property of a question that communicates the entire volume of purge or pore space within the material.
Hence, the porosity of the gravel sample is 28.75%
Learn more about "porosity" :
brainly.com/question/2593663