Liliana can type a 600 word essay in just 8 minutes. how long will it take to type a 2100 word essay

Susan and Mark are standing at different places on a beach and watching a bird. The angles of elevation they make are 20º and 50

Mandarinka [93]

Answer:

The bird is 2.44km high

Step-by-step explanation:

Hello,

To solve this question, we need to understand how they are and we can only get this with a correct pictorial diagram.

See attached document for better understanding.

From the first diagram, we understand that the bird is between them and also on top of them.

Assuming Susan, Mark and the bird all form a triangle at each other and the bird at the top, we can divide the the triangle into two equal parts.

But before then, we should know that sum of angles in a triangle is equal to 180°

Therefore,

20° + 50° + b° = 180

70° + b = 180

b = 180° - 70°

b = 110°

Dividing angle b into two equal parts = 55° on each side.

See the last attached document for better illustration.

Using SOHCAHTOA, we can find the adjacent of the triangle which corresponds to the height of the bird.

We have opposite = 3.4km and we're looking for adjacent. We can use tangent of the angle to find the adjacent.

Tanθ = opposite / adjacent

Tan 55° = 3.5 / adj

Adjacent = 3.5 / tan55

Adjacent = 3.5 / 1.43

Adjacent = 2.44km

The height of the bird is 2.44km

7 0

3 years ago

(6x −9)3−1=((6x−9)3)(0) Solve for X

Tasya [4]

Answer:

Step-by-step explanation:

Remark

Anything multiplied by 0 = 0. So the whole right side is 0.

(6x - 9)*3 - 1 = 0 Add 1 to both sides.

(6x - 9)*3 - 1 + 1 = 0 + 1 Combine

(6x - 9)*3 = 1 Divide both sides by 3

(6x - 9)*3/3 = 1/3 Simplify

(6x - 9) = 1/3 Remove brackets. Add 9 to both sides

6x - 9+9 = 9 1/3 Combine

6x = 9 1/3

6x = 28/3 Divide both sides by 6

6x / 6 = 28/3 // 6 Invert the 6 and multiply.

x = 28/3 * 1/6

x = 28/18

Answer

x = 14/9

6 0

2 years ago

Sort the cities from closest to farthest from sea level. Please help me

dimaraw [331]

I think
J,BB,S

(I shortened name to letter)

5 0

3 years ago

The Town of Hertfordshire clerk knows that 23% of dogs in the town have completed emotional support training. Hertfordshire plan

Nataly_w [17]

Answer:

95.64% probability that under 30% of the dogs are emotional support trained

Step-by-step explanation:

For each dog, there are only two possible outcomes. Either they have completed emotional support training, or they have not. So we use the binomial probability distribution to solve this problem.

However, we are working with samples that are considerably big. So i am going to aproximate this binomial distribution to the normal.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .