A b c or d this one had me confused

What two things can make a molecule polar?

Dafna11 [192]

Answer:

Polar molecules must contain polar bonds due to a difference in electronegativity between the bonded atoms.

Explanation:

3 0

3 years ago

A researcher performs an experiment to test a hypothesis that involves the nutrients niacin and retinol. She feeds one group of

julsineya [31]

Answer:

- 100 grams of food A (x)

- 60 grams of food B (y)

Explanation:

According to this question, the group of laboratory rats are being fed a daily diet of:

- 125.6 units of niacin and 5,400 units of retinol

Let x represent the number of grams needed for food A.

Let y represent the number of grams needed for food B.

This means that:

Food A: Niacin = 0.86x, Retinol = 30x

Food B: Niacin = 0.66y, Retinol = 40y

Since there are 125.6 units of niacin fed to the rats in total, then;

0.86x (A) + 0.66y (B) = 125.6

Since there are 5400 units of retinol fed to the rats in total, then;

30x (A) + 40y (B) = 5400

Solving these two equations simultaneously using elimination method:

0.86x (A) + 0.66y (B) = 125.6 ........(eqn 1)

30x (A) + 40y (B) = 5400 ............ (eqn 2)

Multiply eqn 1 by 30 and eqn 2 by 0.86

30 × 0.86x + 0.66y = 125.6

0.86 × 30x + 40y = 5400

25.8x + 19.8y = 3768 ............ (eqn 3)

25.8x + 34.4y = 4644 ........... (eqn 4)

Subtract eqn 3 from eqn 4

14.6y = 876

Divide both sides by 14.6

y = 876/14.6

y = 60

Substitute value for y (60) into eqn 2

30x + 40y = 5400

30x + 40(60) = 5400

30x + 2400 = 5400

30x = 5400 - 2400

30x = 3000

x = 3000/30

x = 100

Therefore, she feeds the group of rats 100grams of food A (x) and 60 grams of food B (y).

4 0

3 years ago

Create a publication that will explain the evolution of taxonomy and the six kingdoms

lakkis [162]

Answer:

Traditionally, some textbooks from the United States and Canada used a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea/Archaebacteria, and Bacteria/Eubacteria) while textbooks in countries like Great Britain, India, Greece, Brazil and other countries use five kingdoms only (Animalia, Plantae, Fungi, Protista and Monera).

Some recent classifications based on modern cladistics have explicitly abandoned the term "kingdom", noting that the traditional kingdoms are not monophyletic, i.e., do not consist of all the descendants of a common ancestor.

8 0

3 years ago

What should you do if every dilution of your sample results in a plate that is too few to count (tftc)?

lyudmila [28]

When every dilution of your sample results in a plate that is too few to count we should filter the original sample and use most probable number method .

Probable number method count and determine the number of bacteria in a culture, plate aliquots of the dilutions onto agar with sterile pipettes, spread with glass sticks, incubate at 37°C and count the number of colonies. It is imperative that you utilize your best culture technique.

Not all bacterial cells produce colonies, as some bacteria tend to clump or aggregate, and some are nonviable. For this reason results are reported as colony forming units (CFU)/ml of bacterial culture. Ideally only plates with 25-250 colonies are used.

To learn more about bacteria , here

brainly.com/question/8008968

#SPJ4

5 0

2 years ago

Divers have been successfully sent to a depth of 17,000 by the:

harina [27]

Hi There!

Question - Divers have been successfully sent to a depth of 17,000 by the:

Answer - French

Why - Invention of the submarine by a Frenchmen.

Hope This Helps :)