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3 years ago

What did the greeks call the mineral they found and why?

1 answer:

6 0

Ancient civilizations had a high demand for raw materials, like clay, diverse rocks and, most of all, metals. These were required for buildings, crafts, agriculture, their armed forces, financial concerns, art and culture. Clays and rocks produced by opencast mining primarily served for the production of bricks and building blocks, which were used for civil and hydraulic engineering.

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Please answer these questions for me! I am giving MAX points! Brainliest!

guajiro [1.7K]

I think you have them all marked correctly

7. They carry hereditary material from parent

8. 50 percent

1. Nutrition

2. X-linked dominant

If Im wrong Im sorry. its been like 4 years since i took biology but i remember some things

3 0

3 years ago

Read 2 more answers

What is the science of how geothermal energy is collected?

Aleksandr-060686 [28]

........................

3 0

3 years ago

Need an answer, please need an answer, please

Karolina [17]

9514 1404 393

Answer:

moderate low: 82
moderate high: 112.75
vigorous low: 123
vigorous high: 174.25

Explanation:

When calculations are repetitive, I find it convenient to use a calculator that can work with tables.

The PMHR is (220 -15) = 205.

Each of the other heart rates is computed as the formula shows. For example, the low moderate heart rate is 205×0.40 = <u> 82 </u> bpm

The other rates are shown in the attached table. They are computed the same way.

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3 years ago

Suppose that you make a series RC circuit with a capacitor and a known resistor that has a 5% tolerance: R= 5.20 ± 0.26kΩ. You p

Masja [62]

Answer:

correct answer is C

Explanation:

The time constant of an RC circuit is

τ = RC

so to find the capacitance

C = τ/ R

C = 2.150 / 5.20 10³

C = 4.13 10⁻⁴ F

to find the error we use the worst case

ΔC = | $|\frac{dC}{d \tau }| \ \Delta \tau + | \frac{dC}{dR} | \ \Delta R$

the absolute value guarantees that we find the worst case, we evaluate the derivatives

ΔC = 1 /R Δτ + τ/R² ΔR

the absolute values of the errors are

Δτ = 0.002 s

ΔR = 0.3 kΩ

we substitute

ΔC = 0.002 /5.20 10³ + 2.150/(5.20 10³)² 0.3 10³

ΔC = 3.8 10⁻⁷ + 1.74 10⁻⁵

ΔC = 1.77 10⁻⁵ F

the uncertainty or error must be expressed with a significant figure

ΔC = 2 10⁻⁵ F

the percentage error is

Er% = $\frac{\Delta C}{C} \ 100$

Er% = $\frac{2 \ 10^{-5} }{ 4.13 \ 10^{-4} } \ 100$

Er% = 4.8%

the correct answer is C

3 0

3 years ago

Opposite electric charges will repel, and like charges will attract.

DochEvi [55]

As it stands now, that statement is false.

There are two ways to make the statement true:

#1). Exchange the places of the words "Opposite" and "like".

#2). Exchange the places of the words "repel" and "attract".

Either ONE of these changes will make the statement true.
Doing BOTH of these changes will leave it false.

5 0

3 years ago