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Nesterboy [21]
3 years ago
13

The PC modem was invented in what year?​

Chemistry
1 answer:
Andrew [12]3 years ago
5 0

Answer:

1977

Explanation:

Getting connected: a history of modems. Then, in 1977, Dale Heatherington and Dennis Hayes created the world's first PC modem, the 80-103A.

You might be interested in
Night visin cameras are sensitive to energies around 2.21 x 10-19 J. What wavelength of electromagnetic radiation do they use?
defon

Answer:

8.99×10^-7m

Explanation:

The wavelength can be calculated using the expression below

E=hcλ

Where E= energy= 2.21 x 10^-19 J.

C= speed of light= 3x10^8 m/s

h= planks constant= 6.626 × 10^-34 m2 kg / s

E=hcλ

λ= E/(hc)

Substitute for the values

λ=( 2.21 x 10^-19 )/(6.626 × 10^-34 × 3x10^8 )

= 8.99×10^-7m

6 0
3 years ago
*blank* carry blood away from the heart, while *blank* carry blood back to the heart.
worty [1.4K]

Answer:

i think its C im not so sure

Explanation:

nrjdkfkzhsugogo

5 0
3 years ago
Here's a one-batch sample of Just Lemons lemonade production. Determine the percent yield and amount of leftover ingredients for
Bumek [7]

the percent yield is 95% and the excess ingredients are sugar and water but i don't know the amounts. pls let me know if you do :(

4 0
3 years ago
8. A sample of potassium chlorate (KCIO,) was heated in a test tube and decomposed 2KC?(s) 302 (g) + 2KCIO, (s) The oxygen was c
dangina [55]

Answer:

Partial pressure of O_{2} in the gas was 733 torr and mass of KClO_{3} in the sample was 2.12 g.

Explanation:

a) Total pressure of gas = (partial pressure of water vapour)+(partial pressure of O_{2})

Here partial pressure of water vapour is 21 torr and total pressure of gas is 754 torr.

So, partial pressure of O_{2}= (total pressure of gas)-(partial pressure of water vapour) = (754 torr) - (21 torr) = 733 torr

b) Lets assume that O_{2} behaves ideally. Hence-

                                            PV=nRT

where P is pressure of O_{2}, V is volume of O_{2} , n is number of moles of O_{2} , R is gas constant and T is temperature in kelvin

here P = 733 torr = (733\times 0.001316)atm = 0.9646 atm

        V = 0.65 L, R = 0.082 L.atm/(mol.K), T=(273+22)K = 295 K

   So, n=\frac{PV}{RT}

                   = \frac{(0.9646 atm)\times (0.65 L)}{(0.082 L.atm/(mol.K))\times (295 K)}

                   = 0.0259 moles

As 3 moles of O_{2} are produced from 2 moles of KClO_{3} therefore 0.0259 moles of O_{2} are produced from (\frac{2\times 0.0259}{3}) moles or 0.0173 moles of KClO_{3}.

Molar mass of KClO_{3}= 122.55 g

So mass of KClO_{3} in sample = (0.0173\times 122.55)g

                                                                    = 2.12 g

7 0
3 years ago
Feldspars producing clay is an example of ___
BaLLatris [955]

Answer: A

Explanation:

Hydrolysis reactions break down not only feldspars but many other silicate minerals as well, amphiboles, pyroxenes, micas, and olivines.

3 0
3 years ago
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