9th grade science here, please help will mark brainliest

Answer:

b

Explanation:

your welcome :)

Answer:

Radioactive Dating

Explanation:

To get the age range of rocks or fossils, researchers usually make use of radiometric dating technique which is also called radioactive dating. Now, this radioactive dating is based on the principle of comparison between the abundance that's observed from a naturally occurring radioactive isotope including its decay products, with the use of known decay rates.

Answer:

75km/hr

Explanation:

distance(d)=150km

time(t)=2hours

speed=distance/time

=150/2

=75km/hr

Answer:

Eliminate D as there is no nonconservative force, then look at each energies before and after. The speed of the book will increase, so kinetic energy is increasing. The height of the book is increasing, so gravitational potential energy is increasing. However, since the spring is becoming decompressed, the elastic potential energy is decreasing.

Explanation:

Answer:

it is A

Explanation:

Answer:

When I got this question I had to draw it out so if you have to do that, draw 3 stick figures holding hands, one representing the mother, father, and daughter. Then you write their weights on top of them and then draw an arrow pointing from the father to the mother.

Explanation:

use this formula :

[tex]a_{y}[/tex] = [tex]\frac{Fdadshandy}{msys}[/tex]

then you fill it in :

[tex]a_{y}[/tex] = [tex]\frac{100N}{35.5kg+58.2kg}[/tex]

[tex]a_{y}[/tex] = [tex]\frac{100N}{93.7kg}[/tex]

[tex]a_{y}[/tex] = [tex]1.0672[/tex] [tex]m/s^{2}[/tex]

then you multiply that with the daughters weight :

[tex]T_{2} x= m_{2} a_{y}[/tex]

[tex]T_{2} x = 35.5kg (1.0672 m/s^{2})[/tex]

[tex]T_{2} x = 37.89N[/tex]

and that's the answer :) : 37.89N

Answer:I had two questions: 1) Shouldnt the equation be : Change of internal energy= Change in Ke or KEi +Ui=KEf+Uf .. I cant seem to understand how the change in KE+ Change in Internal Energy equals 0 2) Also, it has a note which says that if the bullet alone was chosen as a system, then work would be done on it and the heat transfer woudl occur. How would one formulate an equation for this?

Explanation:

Answer:

concave mirror

Explanation:

Answer:

is highly motivated

Explanation:

Answer:The voltage V in volts (V) is equal to the current I in amps (A) times the resistance R in ohms (Ω): V (V) = I (A) × R (Ω) The power P in watts (W) is equal to the voltage V in volts (V) times the current I in amps (A): P (W) = V (V) × I (A) AC Ohm's law calculator.

Explanation:

40 ampere current passes through a 1 kW heater with 25 Voltage across it.

The difference in electric potential between two places is known as voltage, often referred to as electric pressure, electric tension, or potential difference. It relates to the amount of labor required to transfer a test charge between two places in a static electric field.

Given that power of the source is 1 kW and voltage is 25 V

current is given as,

Power = Voltage*Current

1kW = 25*Current

Current = 1000/25 = 40 ampere.

40 ampere current passes through a 1 kW heater with 25 Voltage across it.

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Answer:

Spectrum because it could respond to a specific color based upon how you humans typically perceive Lights of the wavelength

Answer:

spectrum

Explanation:

Answer:

29.41%

Explanation:

Given that,

In 1630 at the beginning of European settlement, about 425,000,000 hectares of the United States were covered with trees.

By 2017, the area covered by trees was reduced to 300,000,000 hectares.

We need to find the percentage decrease in the area covered by trees between 1630 and 2017.

The percentage decrease in any value is given by :

[tex]\%=\dfrac{300,000,000 -425,000,000 }{425,000,000 }\times 100\\\\=29.41\%[/tex]

So, the percentage decrease in the area covered by the trees is 29.41%.

Answer:

Yes.

Explanation:

Yes, we emphasize performance over participation of kids in a competition which causes negative effect on kid's personality. We also prefer those children whose families can afford the fees which is our big failure. We should  emphasize participation over performance and prefer those child who has the ability to win the game instead of those who can afford the fees.

Answer:

hope this answers will help you

Explanation:

If you find it appropriate then plz mark as brainliest

Answer:

Option B 400meters

Explanation:

What is displacement

Displacement is a vector whose length is the shortest distance from the initial to the final position of a point P undergoing

Given data

number of laps = 2

length of lap= 400meters

Since after every one lap she returns to her initial position ]

the displacement is 400meters

Answer:

Explanation:

how far around a circle is once around in degees?

1.5 * 360 = 540°

Answer:

(i) It was the first such model was supported by scientific evidence: FALSE

(ii) It was not published until Copernicus was close to death: TRUE

(iii) It was the first time a heliocentric model had ever been suggested: FALSE

(iv) It was not controversial, and was readily accepted: FALSE

(v) It stated that the Sun revolved around the Earth: FALSE

(vi) It stated that the Earth revolved around the Sun: TRUE

Explanation:

We proceed to demonstrate the validity of each option from statement:

(i) It was the first such model was supported by scientific evidence: FALSE

The geocentric model was based mostly on interpretation of two astronomical findings: (a) The displacement of the stars with respect to Earth due to stellar parallax, (b) The apparent consistency of brightness of the planet Venus seen from Earth.

(ii) It was not published until Copernicus was close to death: TRUE

Copernicus published his heliocentric theory, contained in the book De revolutionibus orbium coelestium, months before his death, in 1543.

(iii) It was the first time a heliocentric model had ever been suggested: FALSE

Greek mathematician and astronomer Aristarchus of Samos was the first person who proposed the heliocentric model in the 4th Century.

(iv) It was not controversial, and was readily accepted: FALSE

The Roman Catholic Church defended geocentric model proposed by Claudius Ptolemy and Tycho Brahe and rejected the model proposed by Copernicus, whose publication was included in the Index Librorum Prohibitorum in 1616.

(v) It stated that the Sun revolved around the Earth: FALSE

This is the main idea of the geocentric model.

(vi) It stated that the Earth revolved around the Sun: TRUE

This is the main idea of the heliocentric model.

Answer:

0.55 m/s².

Explanation:

From the question given above, the following data were obtained:

Mass (m) of ball = 2 Kg

Force (F) applied = 1.1 N

Acceleration (a) =?

Force (F) is defined as the product of mass (m) and acceleration (a). Mathematically, the force (F) can be represented as:

Force (F) = mass (m) × acceleration (a)

F = ma

With the above formula, we can calculate the acceleration of the ball as follow:

Mass (m) of ball = 2 Kg

Force (F) applied = 1.1 N

Acceleration (a) =?

F = ma

1.1 = 2 × a

Divide both side by 2

a = 1.1 / 2

a = 0.55 m/s²

Therefore, the acceleration of the ball is 0.55 m/s²

Answer:

Explained below

Explanation:

When we eat food, our body gets chemical energy from it. Now, this chemical energy from the food is changed into some different energy forms that is useful to it. They include:

-Chemical to mechanical energy to aid in movement of muscles

- chemical to thermal energy to aid in regulating the body temperature.

- chemical to electrical energy to aid the brain in thinking.

Thus is similar to how a machine converts energy because machines also generate energy after being powered and convert to other forms of energy. For example, an alarm clock converts electrical energy to sound energy, hair dryer converts electrical energy to thermal/heat energy.

Answer:

A different answer to this is AI

Explanation:

Lithium, beryllium and boron are the elements that have an oxidation number of +3.

Oxidation number refers to the total number of electrons that an atom gains or loses in order to get stability and formed chemical bond with another atom. Atoms that lose electron form positive charge.

So we can conclude that Lithium, beryllium and boron are the elements that have an oxidation number of +3.

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Answer:

A) Mass in air is unrelated to altitude

Explanation:

Mass is the amount of matter contained in a substance. Altitude is the height of a body above a reference plane.

Mass and altitude are unrelated.

Answer:

Hiiiiiiii........where r u frm??

Answer:   Natural stone

Explanation:

Answer:

Natural stone

Explanation:

The most common natural stones used to make countertops include granite, marble, soapstone, and slate.

Answer:

B. It can be answered using measurements.

Explanation:

Scientific inquiry can be defined as the various ways, techniques and approach used by scientists to study the world and provide a detailed description (information) based on the empirical evidence derived from the investigation.

Measurements can be defined as a technique which typically involves the process of identifying and determining the dimensions, quality and quantity of a physical object.

Hence, the statement which best describes a characteristic of a question that can be answered through scientific inquiry is that, it can be answered using measurements. Using scientific inquiry to answer questions entails using measurements to propose specific and evidential explanations, as well as back up theories associated with the question.

Answer:

periodic motion

Explanation:

The massive object is affectionately referred to as the pendulum bob. When the bob is displaced from equilibrium and then released, it begins its back and forth vibration about its fixed equilibrium position. The motion is regular and repeating, an example of periodic motion.

Answer:

Without volcanoes, most of Earth's water would still be trapped in the crust and mantle . Early volcanic eruptions led to the Earth's second atmosphere, which led to Earth's modern atmosphere . Besides water and air, volcanoes are responsible for land, another necessity for many life forms .

Explanation:

Answer:

Explanation:

Prescribe medications.

Prescribe treatments or therapies.

Treat patients using psychological therapies.

Collect medical information from patients, family members, or other medical professionals.

Record patient medical histories.

Develop medical treatment plans

Answer:assisting and caring for others

making decisions and solving problems

getting information

Explanation:

I'm pretty sure about the answer. Thank you