a
a decrease in the number of zebra mussels along the waterways
b
an increase in the number of zebra mussels along the waterways
c
no effect because more time is needed to determine an outcome
d
no change in the number of zebra mussels infecting the waterways

Scientists approximate that there are 20 billion stars like our sun in the Milky Way.
Why does the sun appear to be brighter than any other star in the Milky Way?
A.the sun is older than all of the other stars in the Milky Way
B.the sun is closer to the earth than any other star in the Milky Way
C.the sun is hotter than any other star in the Milky Way
D.the sun has more energy than any other star in the Milky Way

The picture shows a spoonful of salt being added to a glass of water. What physical property of the salt is being demonstrated?A.
A.
solubility

B.
density

C.
boiling point

D.
melting point

What type of erosion cause a canyon form?
water
wind
ice

Please help me answer these questions

Fill in the chart to identify how scientists represent matter and chemical changes in matter.

What is the average thermal energy of ice?

This is about rocks and/or minerals

A fireman feels the heat from a fire before he even gets up to it. This is caused by ___.

a conduction
b convection
c radiation

Which property of physical changes explains why matter is conserved in a physical change? The arrangements of particles do not change, and the bonds between atoms do not break.
Mass, not energy changes in a physical change.
Energy and mass change in a physical change.
The bonds between atoms do not break, it's only the arrangement that changes.​

Is this a scientific model? Use complete sentences to explain why or why not



Public Domain

PLS HELP I AM CONFUSED!!!!!!!THESE ARE ALL THE PIONTS I HAVE LEFT!!!

The student mixed up 500ml of salt solution. He weight it and found it mass to be 585g. will his shake up toy work the way that he want it to work?why or why not?

Remember, 1 mL = 1cm

Show your math

Drinking water has two sources. It can come from surface water, such as reservoirs or rivers. Or it can come from groundwater where it either naturally surfaces in a spring or where it must be pumped to the surface from a well. Where does your drinking water come from?

Stephen pours a glass of ice water. He gets a phone call before he can drink it. What will happen if he leaves the glass on the counter for 2 hours?

a heat will transfer from the water to the ice until both reach the same temperature
b heat will transfer from the water to the ice until the water is colder than the ice
c heat will transfer from the ice to the water and the ice will stay colder than the
water.
d heat will transfer from the ice to the water and the ice will get warmer than water

Order the list of Earth’s water resources from greatest to least: Rivers; Ocean water (salt); Ice Caps/glaciers; Groundwater

how the remains of plants and animals become fossil fuels. why are they considered nonrenewable resources

Which set of diagrams shows a balanced chemical equation?
A: 2 H, 2 O, 2 S and 2 H, 2 O, 3 S. B: 4 H, 2 O, 3 S and 4 H, 2 O, and 1 S. C: 4 H, 2 O, 2 S and 4 H, 2 O, 2 S. D: 2 H, 2 O, 2 S and 1 H, 1 O, 1 S.
A. Diagram A
B. Diagram B
C. Diagram C
D. Diagram D

label the following as a pure substance or a mixture.

describe what is happening to rock climbers’ body systems and cells at the small scale.

The moon's observed motion across the sky is PRIMARILY due to the
A)
rotation of the moon.
B)
rotation of the earth.
C)
orbit of the moon around the earth.
D)
orbit of the earth around the moon.

computers can turn electrical energy into light and sound energy. which other type of energy does a computer produce
A. Thermal Energy
B. chemical energy
C. magnetic energy
D. gravitational energy

Terrence measures the amount of water displaced by various objects when they are dropped into a graduated cylinder of water. By looking at his data, he realizes that the amount of water displaced depends on either the mass or the volume of the object, depending on whether the object sinks or floats.

Which data table includes all the information Terrence needs to come to this conclusion?

Thomas thinks that acceleration means “speeding up.” Explain why this is incorrect.

A boat is traveling to the right at 300 N, the current is going to the left at 600N. What is the net force and direction?

The invention of the _____________ was considered the critical invention for easily classifying and organizing Stars by brightness, color, and temperature


Radio Telescope


HR Chart (Hertzsprung- Russell)


Infra red Camera

Nasa Star Modeling Programs

If the force squeezing two surfaces together is decreased, the force of friction between the two surfaces will most likely what?

I NEED HELP WITH BOTH OF THESE!!!!!!

Study the image of Earth’s layers. Cross section of layers of the Earth. Inner core equals 1,216 kilometers; Outer core equals 2,270 kilometers. Mantle equals 2,885 kilometers, and consists of lower and upper mantle. Upper mantle is made up by: Asthenosphere at 660 kilometers, Lithosphere at 100 kilometers, Oceanic crust at 5 kilometers, Continental crust at 30 to 40 kilometers. Which statement correctly compares the thicknesses of Earth’s layers? Earth’s mantle is thinner than its oceanic crust. Earth’s outer core is thicker than its mantle. Earth’s continental crust is thicker than its lithosphere. Earth’s lithosphere is thinner than its asthenosphereStudy the image of Earth’s layers.

PLS HELP THIS IS URGENT LIKE AN ASPA QUESTION THAT NEEDS AND ANSWER PLS HELP
Describe the percentages of electromagnetic energy that comes from the sun?

Can someone help me ask a dude out ?

Describe the percentages of electromagnetic energy that comes from the sun