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lutik1710 [3]
3 years ago
9

URGENT! Please help me with 7-9 and if possible can you please explain why :)!

Physics
1 answer:
faust18 [17]3 years ago
8 0
7) c
opposite charges attract, equal charges repell
8) c
Followed from equation
9) d
Same reason as under 7
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Ecoststem with the harshest climate​
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Tundra

The tundra is an ecosystem that is considered the harshest ecosystem on earth. It is a treeless region whose climate is characterized by being cold, snowy, and windy with very little rainfall. It is covered in snow for most of the year.

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A star is located at a distance of about 100 million light years from Earth. An astronomer plans to measure the distance of the
nlexa [21]
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An iceberg is 3,000 metres from a submarine. The submarine emits ultrasound. How long until the submarine detects the iceberg?
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3 0
3 years ago
Read 2 more answers
Twin​ brothers, Andy and​ Brian, can mow their​ grandparents lawn together in 1212 minutes. Brian would mow the lawn by himself
Karo-lina-s [1.5K]

Answer:

It will take Andy 1.198minutes to mow the lawn and it will take Brian 1,209.98minutes to mow the same lawn.

Step-by-step explanation:

Using the simultaneous equation concept, let A denote Andy and B be Brian

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If Brian would mow the lawn by himself in 1010 minutes more than it would take Andy, this means B=1010A...eqn 2.

Substituting eqn 2 into eqn 1

Equation 1 becomes

A+1010A=1212

1011A=1212

A=1212/1011

A=1.198

B = 1010×1.198

B=1,209.98

Therefore, It will take Andy 1.198minutes to mow the lawn and it will take Brian 1,209.98minutes to mow the same lawn.

6 0
3 years ago
Is there more than one universe that can be explained?
Firlakuza [10]

No.  We don't know of the existence of another universe besides
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7 0
4 years ago
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