Answer:
Every week, the radioactivity decreases by a factor of 5
After 1 week, it goes from 5,000 to 1,000
2 weeks 1,000 / 5 =200
3 weeks 200 / 5 = 40
4 weeks 40 / 5 = 8
5 weeks 8 / 5 = 1.6
6 weeks 1.6 / 5 = 0.064
7 weeks 0.064 / 5 = 0.0128
8 weeks .0128 / 5 = 0.00256
9 weeks 0.00256 / 5 = 0.000512
10 weeks 0.000512 / 5 = 0.0001024
Step-by-step explanation:
Answer:
The diameter is 13.88 feet.
Step-by-step explanation:
1. The formula for calculate the volume of a sphere is:

Where
is the radius.
2. The diameter is:

3. So, you must solve for the radius in the first equation:
![r=\sqrt[3]{\frac{4(790.272ft^{3} )}{3\pi}}\\r=6.94ft](https://tex.z-dn.net/?f=r%3D%5Csqrt%5B3%5D%7B%5Cfrac%7B4%28790.272ft%5E%7B3%7D%20%29%7D%7B3%5Cpi%7D%7D%5C%5Cr%3D6.94ft)
4. Then, the diameter is:

Answer:
54
Step-by-step explanation:
to evaluate substitute b = 18 into 3b
3b = 3 × 18 = 54
Answer:
(9x²)²
Step-by-step explanation:
Given the expression 81x⁴, to write the expression as a square of a monomial, first we will assign a variable to the expression.
y = 81x⁴
Then we take the square root of both sides of the expression
√y = √81x⁴
y^½ = √81 × √x⁴
y^½ = 9x²
Squaring both sides of the resulting equation to get y back
(y^½)² = (9x²)²
y = (9x²)²
The expression as a square of a monomial is (9x²)²
Answer:
b. Do not reject H0. We do not have convincing evidence that the mean weekly time spent using the Internet by Canadians is greater than 12.7 hours.
Step-by-step explanation:
Given that in a study of computer use, 1000 randomly selected Canadian Internet users were asked how much time they spend using the Internet in a typical week. The mean of the sample observations was 12.9 hours.

(Right tailed test at 5% level)
Mean difference = 0.2
Std error = 
Z statistic = 1.0540
p value = 0.145941
since p >alpha we do not reject H0.
b. Do not reject H0. We do not have convincing evidence that the mean weekly time spent using the Internet by Canadians is greater than 12.7 hours.