Answer:
1. Recollapsing universe
2. Critical universe
3. Coasting universe
Explanation:
Recollapsing universe has dark matter density greater than critical density. While critical universe has its matter density equal to the critical sensity. Coasting universe on the other hand has much smaller matter density compared to critical density.
Note that the critical density is approximately 10^-20 grams/cm3
Echoes occur when a reflected soundwave reaches the ear more than 0.1 seconds after the original sound wave was heard. ... There will be an echoinstead of a reverberation. Reflection of sound waves off of surfaces is also affected by the shape of the surface.
(mark as brainly please)
Answer:
An independent variable is a variable that is manipulated to determine the value of a dependent variable. The dependent variable is what is being measured in an experiment or evaluated in a mathematical equation and the independent variables are the inputs to that measurement.
Explanation:
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Answer:</h3>
Input work
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Explanation:</h3>
Concept being tested: Efficiency of machines
Therefore we need to know what is the efficiency of a machine
- Efficiency of a machine is the ratio of work output of machine to the work input expressed as a percentage.
Efficiency = (Work output ÷ Work input) × 100%
- Therefore, if the work input is equal to the work output then the efficiency of the machine will be 100%.
- Most machines are not 100% efficient due to loss of energy in form of heat due to friction of the moving parts of the machine.
There is a total of 6 half lives that need to take place.
ONE HALF LIFE = 200
TWO HALF LIFES = 100
THREE HALF LIFES = 50
FOUR HALF LIFES = 25
FIVE HALF LIFES = 12.5
SIX HALF LIFES = 6.25
The answer is 6.25g
