PLEASE HELP FAST!

A river discharges 4 × 106 cubic feet of water into the Pacific Ocean each second. There are 86,400 seconds in one day. To find

erik [133]

Answer:

3.456E + 14= $3.456X10^{14$

Step-by-step explanation:

The river discharges $4X10^6$ cubic feet of water into the Pacific Ocean each second.

There are 86,400 seconds in one day.

Amount of water discharges each day

$=4X10^6X86400\\=345600000000\\=3.456X10^{11$

Since this differs from what you have, I will explain the scientific notation.

3.456E + 14 simply means $3.456X10^{14$

The options are not well laid out but you can pick the appropriate option.

8 0

4 years ago

Suppose that the mean water hardness of lakes in Kansas is 425 mg/L and these values tend to follow a normal distribution. A lim

tino4ka555 [31]

Answer:

The mean water hardness of lakes in Kansas is 425 mg/L or greater.

Step-by-step explanation:

We are given the following data set:

346, 496, 352, 378, 315, 420, 485, 446, 479, 422, 494, 289, 436, 516, 615, 491, 360, 385, 500, 558, 381, 303, 434, 562, 496

Formula:

$\text{Standard Deviation} = \sqrt{\displaystyle\frac{\sum (x_i -\bar{x})^2}{n-1}}$

where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

$Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}$

$Mean =\displaystyle\frac{10959}{25} =438.36$

Sum of squares of differences = 175413.76

$S.D = \sqrt{\dfrac{175413.76}{24}} = 85.49$

Population mean, μ = 425 mg/L

Sample mean, $\bar{x}$ = 438.36

Sample size, n = 25

Alpha, α = 0.05

Sample standard deviation, s = 85.49

First, we design the null and the alternate hypothesis

$H_{0}: \mu \geq 425\text{ mg per Litre}\\H_A: \mu < 425\text{ mg per Litre}$

We use one-tailed t test to perform this hypothesis.

Formula:

$t_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{s}{\sqrt{n}} }$

Putting all the values, we have

$t_{stat} = \displaystyle\frac{438.36 - 425}{\frac{85.49}{\sqrt{25}} } = 0.7813$

Now, $t_{critical} \text{ at 0.05 level of significance, 24 degree of freedom } = -1.7108$

Since,

The calculated t-statistic is greater than the critical value, we fail to reject the null hypothesis and accept it.

Thus, the mean water hardness of lakes in Kansas is 425 mg/L or greater.

6 0

3 years ago

Rectangular windows are being made into a wall of windows for an office building. Each wall is 14 feet tall and 12 feet wide. Th

Artemon [7]

Answer:

168/(x² +7x)

Step-by-step explanation:

The height of each window is 14/(x+7), and the width of each window is 12/x. The area of each window is the product of its height ans width:

area = (14/(x+7))(12/x) = 168/(x(x +7))

area = 168/(x² +7x)

_____

<em>Comment on the problem</em>

There is not enough information given to determine suitable values for x. If x is 42, each window is a square 3 3/7 inches on a side.

7 0

3 years ago

Alisha has a $15,000 car loan with a 6 percent interest rate that is compounded annually. How much will she have paid at the end

Tpy6a [65]

6 percent intrest per year for 5 years I think is the same as 30 percent for 5 years

so $15,000 x .3 is $4500

$15,000 + $4500 = $19,500

not 100 percent sure if this is correct but I think its right. Sorry if im wrong.

4 0

3 years ago

Read 2 more answers

Samantha threw an apple from the tenth floor of her apartment

Vilka [71]

Could you put the whole question or the answer choices?

3 0

3 years ago