Answer:
<em>There is no significant difference in the amount of rain produced when seeding the clouds.</em>
Step-by-step explanation:
Assuming that the amount of rain delivered by thunderheads follows a distribution close to a normal one, we can formulate a hypothesis z-test:
<u>Null Hypothesis
</u>
: Average of the amount of rain delivered by thunderheads without seeding the clouds = 300 acrefeet.
<u>Alternative Hypothesis
</u>
: Average of the amount of rain delivered by thunderheads by seeding the clouds > 300 acrefeet.
This is a right-tailed test.
Our z-statistic is
We now compare this value with the z-critical for a 0.05 significance level. This is a value
such that the area under the Normal curve to the left of
is less than or equal to 0.05
We can find this value with tables, calculators or spreadsheets.
<em>In Excel or OpenOffice Calc use the function
</em>
<em>NORMSINV(0.95)
</em>
an we obtain a value of
= 1.645
Since 1.2845 is not greater than 1.645 we cannot reject the null, so the conclusion that can be drawn when the significance level is 0.05 is that there is no significant difference in the amount of rain produced when seeding the clouds.
The answer is 0.45 repeated
Answer:
(5h-4t)(5h+4t)
Step-by-step explanation:
25h² - 16t²
adding and subtracting 20ht from it (√25 and √16 = 5x4 = 20):
25h² + 20ht - 20ht -16t²
factor:
(5h-4t)(5h+4t)

2d +9= 19
The solution is d =

Hello there, first we can place our equation, which you have stated
, this algebra, in algebra we want to find the exact value of the variable, or have the variable on one side of the equation.
First we can subtract
with both sides of the equation giving us the result of
, this can also be represented as
, now just divide both sides of the equation by
, our answer is
.
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<h3><em>Have a good day :) !</em></h3>