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What is the perimeter of the pentagon below? 3.2 cm?

erica [24]

Answer:

You didn't attach a picture of the pentagon, but the perimiter can easily be found using one of the following formulae:

Step-by-step explanation:

P = 5s, where s is the length of a side

P = 2r × Sin(180/5), where r is the radius

4 0

2 years ago

Arsenic is a compound that occurs naturally in very low concentrations. Arsenic blood concentrations in healthy adults are Norma

DENIUS [597]

Answer:

0.7325 to 5.6675 ug/dl

Step-by-step explanation:

The middle 90% will be 45% above the mean and 45% below the mean. This means

0.5-0.45 = 0.05 and

0.5+0.45 = 0.95

We use a z table. Look in the cells; find the values as close to 0.05 and 0.95 as we can get.

For 0.05, we have 0.0505 and 0.0495; since these are equidistant from 0.05, we use the value between them. 0.0505 is z=-1.64 and 0.0495 is z=1.65; this gives us z=-1.645.

For 0.95, we have 0.9495 and 0.9505; since these are equidistant from 0.95, we use the value between them. 0.9495 is z = 1.64 and 0.9505 is z=1.65; this gives us z = 1.645.

Now we use our z score formula,

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

Our two z scores are 1.645 and -1.645; our mean, μ, is 3.2; and our standard deviation, σ, is 1.5:

$1.645=\frac{X-3.2}{1.5}$

Multiply both sides by 1.5:

$1.5(1.645)=\frac{X-3.2}{1.5}\times 1.5\\\\2.4675 = X-3.2$

Add 3.2 to each side:

2.4675+3.2 = X-3.2+3.2

5.6675 = X

$-1.645=\frac{X-3.2}{1.5}$

Multiply both sides by 1.5:

$1.5(-1.645)=\frac{X-3.2}{1.5}\times 1.5\\\\-2.4675=X-3.2$

Add 3.2 to each side:

-2.4675+3.2 = X-3.2+3.2

0.7325 = X

Our range is from 0.7325 to 5.6675.

5 0

3 years ago

Every evening, two weather stations issue weather forecast for the next day. The weather forecasts are independent. On average,

EleoNora [17]

Answer:

The probability is 0.6923

Step-by-step explanation:

Let's call R the event that the next day rains, S the event that the next day has sunny weather, R2 the event that the station 2 predicts rain and S1 the event that station 1 predict sunny weather.

The probability that the next day has sunny weather given that station 1 predicts sunny weather for the next day and station 2 predicts rain is calculated as:

P(S/S1∩R2) = P(S∩S1∩R2)/P(S1∩R2)

Where P(S1∩R2) = P(R∩S1∩R2) + P(S∩S1∩R2)

So, the probability P(R∩S1∩R2) that the next day rains, Station 1 predicts sunny weather and Station 2 predicts Rain is calculate as:

P(R∩S1∩R2) = 0.5 * 0.1 * 0.8 = 0.04

Because 0.5 is the probability that the next day rains, 0.1 is the probability that station 1 predicts sunny weather given that it is going to rain and 0.8 is the probability that station 2 predicts rain given that it is going to rain.

At the same way, the probability P(S∩S1∩R2) that the next day has sunny weather, Station 1 predicts sunny weather and Station 2 predicts Rain is calculate as:

P(S∩S1∩R2) = 0.5 * 0.9 * 0.2 = 0.09

Then, the probability P(S1∩R2) that station 1 predicts sunny weather for the next day, whereas station 2 predicts rain is:

P(S1∩R2) = 0.04 + 0.09 = 0.13

Finally, P(S/S1∩R2) is:

P(S/S1∩R2) = 0.09/0.13 = 0.6923

6 0

3 years ago

Which of these numbers has the highest value? -22, 0.0099, 0, -1, (-1)

Oliga [24]

.0099 is the only positive number above zero and would have the highest value

5 0

3 years ago