Answer:
Number 7.) triangle
Number 8.) Cylinder
Number 3.) Rectangle
Step-by-step explanation:
The first thing you have to do is find a way to make the last digit 6 (since its $56). So that would be $8×2=16, so there are 2 small notebooks. Then, she needs another $40 to get $56, so 40÷10=4, so she bought 4 large notebooks.
Answer: 2 small, 4 large
The number of points Marco needs to bring his average up to 90% is 15points.
If there's a possible 25 possible points, and Marco has taken 5 quizzes;
Evidently, each quiz has weighs 5 points.
Mathematically;
- 2100 + 500x = 2250 + 450x
x = 3.
Therefore, he needs 5x points = 15 points to bring his average up to 90%.
Read more:
https://brainly.in/question/24249798
Answer:
see below
Step-by-step explanation:
The equation for half life is
n = no e ^ (-kt)
Where no is the initial amount of a substance , k is the constant of decay and t is the time
no = 9.8
1/2 of that amount is 4.9 so n = 4.9 and t = 100 years
4.9 = 9.8 e^ (-k 100)
Divide each side by 9.8
1/2 = e ^ -100k
Take the natural log of each side
ln(1/2) = ln(e^(-100k))
ln(1/2) = -100k
Divide each side by -100
-ln(.5)/100 = k
Our equation in years is
n = 9.8 e ^ (ln.5)/100 t)
Approximating ln(.5)/100 =-.006931472
n = 9.8 e^(-.006931472 t) when t is in years
Now changing to days
100 years = 100*365 days/year
36500 days
Substituting this in for t
4.9 = 9.8 e^ (-k 36500)
Take the natural log of each side
ln(1/2) = ln(e^(-36500k))
ln(1/2) = -36500k
Divide each side by -100
-ln(.5)/36500 = k
Our equation in years is
n = 9.8 e ^ (ln.5)/36500 d)
Approximating ln(.5)/365=-.00001899
n = 9.8 e^(-.00001899 d) when d is in days
