Someone please help will mark as brainliest please answer all of the questions

Answer:

1.The main difference between SPECT and PET scans is the type of radiotracers used. While SPECT scans measure gamma rays, the decay of the radiotracers used with PET scans produce small particles called positrons. ... These react with electrons in the body and when these two particles combine they annihilate each other.

2 .A single photon emission computed tomography (SPECT) scan is an imaging test that shows how blood flows to tissues and organs. It may be used to help diagnose seizures, stroke, stress fractures, infections, and tumors in the spine.

3.Uses for PET scan include checking brain function; diagnosing cancer, heart problems, and brain disorders; examining blood flow to the heart; and determining spread of cancer and response to therapy. The use of PET scans may help doctors more accurately detect the presence and location of cancer cells.

4.Stress-only SPECT protocols resulting in lower dosimetry and less time in the imaging laboratory may be appropriate for many patients. PET perfusion imaging offers indisputably better images that are characterized by higher resolution, better attenuation correction, less scatter, and better contrast

Hope I wasn't too late.

A radio station transmits to a receiving antenna. The radio wave sent is a

a.
surface wave
b.
torsional wave
c.
longitudinal wave
d.
transverse wave

The diagram below shows a longitudinal wave at one instant in its motion. Each oval represents a particle acted on by the energy of the wave as it moves from left to right.

Which line on the diagram indicates a region of rarefaction?

Composed of two flat pins or flat holes for the live and neutral wire, commonly found in the household here in the Philippines.
A.)Fuse
B.)circuit breaker
C.)Type A electrical plug or outlet
D.)Type B plug or outlet

Science subject

Please answer these. The tables needed for question 7 are in the picture. I got rid of some of the questions that you wouldn’t be able to answer without doing the lesson

Question 1: Electron Notation Example (2 points)

a. Give the electron configuration of vanadium (V), atomic number 23. (0.5 points)

b. Give the noble gas configuration of vanadium (V), atomic number 23. (0.5 points)

c. List the energy levels for the orbital configuration of vanadium (V), atomic number 23. (1 point)

Question 3: Trends on the Periodic Table (2 points)
a. How does the atomic radius change going down and across the periodic table? (0.5 points)

b. How does first ionization energy change going down and across the periodic table? (0.5 points)

c. How does electronegativity change going down and across the periodic table? (0.5 points)

d. How does the radius of a positive and negative ion compare to a neutral atom? (0.5 points)

Question 4: Chemical Bonds (1 point)
Match each chemical bond to its correct description. (1 point)
A. Ionic bond ___ Sharing of electrons
B. Covalent bond ___ Freely moving electrons
C. Metallic bond ___ Transfer of electrons
Question 5: Intermolecular Forces (3 points)

a. Describe the dipole-dipole force. (1 point)

b. Describe hydrogen bonding. (1 point)

c. Describe the Van der Waals forces. (1 point)

Question 6: Intermolecular Forces and You (2 points)
Imagine you need to take a medicine that the doctor has prescribed for you. Explain why scientists who developed that medicine would need to know whether or not the compound in that medicine is polar. How might a polar medicine behave differently within your body than a nonpolar medicine would? Answer in 1 to 2 paragraphs.

Question 7: Energy in Bonds (9 points)
Use these tables for reference for all parts of this question.

This table summarizes the average energies of single bonds between atom pairs in many different compounds.
a. According to Table 2, which is the strongest bond? Which is the weakest bond? Based on what you know about the atomic radii and electronegativity of the elements involved in the bonds, why do you think these two have the most extreme bond-energy values? (3 points)

b. How are the bond energies of each bond listed in Table 2 determined? (1 point)

c. Why do you think there aren't bond energy values given in Table 2 for N–S and S–I? (1 point)

d. Based on Tables 1 and 2, how would you describe the trend in bond strength of single, double, and triple bonds? (1 point)

e. Based on Table 2, how would you describe the trend in the strength of bonds formed by the elements carbon, nitrogen, and oxygen? Would you describe this trend as a periodic trend? Why or why not? (3 points)

Question 8: Causes of Molecular Shape (3 points)
a. What is the VSEPR theory? (1 point)

b. How does electron repulsion determine molecular shape? (1 point)

c. How do lone electron pairs affect molecular shape? (1 point)

Question 10: Lewis Structure (3 points)
a. Draw the Lewis structure for the Se and 2 H atoms. (1 point)

b. Draw the Lewis structure for the SeH2 molecule. (1 point)

c. What shape would SeH2 have? Draw the molecule. (1 point)

Question 11: Ionic and Covalent Compounds (5 points)
Identify each of the following as a covalent compound or ionic compound. Then provide either the formula for compounds identified by name or the name for those identified by formula. (1 point each)
a. Li2O:

b. Dinitrogen trioxide:

c. PCl3:

d. Manganese(III) oxide:

e. Calcium bromide:

true or false, during a change of state, the thermal energy gained or lost by a material changes the kinetic energy of its particles

1. Which of the following substances is believed to be responsible for the hole in the ozone
layer?
A. Ammonia
B. Chlorofluorocarbons (CFCs)
C. Lead
D. Carbon monoxide

When a surface is experiencing friction with another surface, how are the particles
affected? How will the temperature of the surface change?
Prediction

What do you think it means to "use safe cooking practices?"​

the diagram shows a race car traveling around the racetrack at a constant speed of 150km/hr. at which point on the track is the car accelerating

A diver's tank contains helium at 924 psi,
nitrogen at 1456 psi and oxygen. The total
pressure is 2803 psi. What partial pressure is
exerted by the oxygen?

Please answer correctly !!!!!!!!!!!!! Will mark Brianliest !!!!!!!!!!!!!!!!!

I will give you Brainly if you awsers right pl if your gonna awser for pints just put I don’t know

Think about how particles are arranged inside atoms. Please name and describe those three particles, and describe how the particles are arranged inside atoms. Some topics to include are: the charge of the particles, the mass of the particles, and where the particles are located.

Which of the below elements will not likely form an ionic bond?
A.
Cs & O
B.
P & O
C.
Ne & Cl
D.
Li & Mg

A rocket will rotate about a single point called the _?

Observe: Look at the red lithium atom and the blue oxygen atom. Recall that most atoms are stable when their outermost ring has eight electrons. (Some atoms, such as lithium and beryllium, are stable when their outermost ring has two electrons.)

How many electrons will the lithium atom give up to become stable?

1. eight

2. seven

3. two

4. one

What happens when the two atoms are Too close

Which is an example of an exothermic reaction?

A. the rusting of iron
B. dissolving ammonium chloride in water C. photosynthesis
D. baking bread​

What would be one way to avoid static electricity? А) Dry cotton fabrics and synthetic fabrics separately. B) Run a metal clothes hanger across your dry hair. C Use a blow dryer to dry your hair. D Wear shoes with rubber soles.​

Carbon tetrafluoride, CF, contains four identical C-F bonds. Fluorine is more
electronegative than carbon. How will this impact each of the bonds between carbon and
fluorine?
a. The electrons in each C-F bond will be more attracted to the carbon atom.
b. The electrons in each C-F bond will be attracted equally to both atoms.
C. The electrons in each C-F bond will be more attracted to the fluorine atom.
d. The electrons in each C-F bond will separate easily.

Can someone plz help me with this plz?????

What is the formula for Iron (III) Bromate
​

How many molecules of nitrogen dioxide gas (NO2) are present in 15 liters of the gas at STP?

When turgor pressure is high enough in a cell, the cell walls become _____

True or False: The only planet that has gravity is the Earth.
O True
False

Help please:)

Calculate the atomic mass of copper if copper-63 is 69.17% abundant and copper-65 is 30% abundant

What quantity is needed to convert between the moles of a
given sample of a substance and its mass in grams?
a the molar mass of the substance
b the density of the substance
с
the physical state of the substance
d all of the above
Check it

A compound is 39.97% carbon, 13.41% hydrogen, and 46.62% nitrogen. What is the empirical formula?

write the name of the first twenty elements with their symbols and their atomic number​

Matter is anything that takes up _______, has _______, and is made up of particles.