The temperature of the ice cream 2 hours after it was placed in the freezer is 37.40 °C
From Newton's law of cooling, we have that

Where





From the question,


∴ 

Therefore, the equation
becomes

Also, from the question
After 1 hour, the temperature of the ice-cream base has decreased to 58°C.
That is,
At time
, 
Then, we can write that

Then, we get

Now, solve for 
First collect like terms


Then,


Now, take the natural log of both sides


This is the value of the constant 
Now, for the temperature of the ice cream 2 hours after it was placed in the freezer, that is, at 
From

Then






Hence, the temperature of the ice cream 2 hours after it was placed in the freezer is 37.40 °C
Learn more here: brainly.com/question/11689670
Answers:
- a) 693 sq cm (approximate)
- b) 48 sq cm (exact)
============================================================
Explanation:
Part (a)
A regular triangular pyramid, aka regular tetrahedron, has all four triangles that are identical copies of one another. They are congruent triangles. This will apply to part (b) as well.
To find the area of one of the triangles, we'll use the formula
A = 0.25*sqrt(3)*x^2
where x is the side length. This formula applies to equilateral triangles only.
In this case, x = 20, so
A = 0.25*sqrt(3)*x^2
A = 0.25*sqrt(3)*20^2
A = 173.20508 approximately
That's the area of one triangle, but there are four total, so the entire area is about 4*173.20508 = 692.82032 which rounds to 693 sq cm.
The units "sq cm" can be written as "cm^2".
----------------------------
Part (b)
We'll use the same idea as part (a). But the formula to find the area of one triangle is much simpler.
The area of one of the triangles is A = 0.5*base*height = 0.5*6*4 = 12 sq cm.
So the area of all four triangles combined is 4*12 = 48 sq cm
This area is exact.
The area of each 2D flat net corresponds exactly to the surface area of each 3D pyramid. This is because we can cut the figure out and fold along the lines to form the 3D shapes.
It's actually easier than it seems. if the tax is paid in equal payments every month and the total throughout a year (12 months) is $2,820, you have to find out how much they pay every month
so divide the total by the number of months
2,820/12=235
they pay $235 in taxes every month
to find out the total of the taxes and the house payment, just add the monthly tax and the monthly house payment.
235+752
and your answer is the sum
Answer:
18581.16
Step-by-step explanation:
The area of each of the shale can be calculated as
distance between each point = x
The area of the regular Dodecahedron
A = ![\sqrt[3]{25+10\sqrt{5} } a^{2}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B25%2B10%5Csqrt%7B5%7D%20%7D%20%20%20a%5E%7B2%7D)
where a = number of edges = 30
hence the area of the regular dodecaheron = 18581.16