False, Carbon usually forms four covalent bonds.
Mass extinction occur from natural disasters, such as a n asteroid hitting earth or a volcano errupting and spread ash everywhere.
It makes sense to measure geologic time between mass extinctions because after each mass extinction, there is almost no life left and the few left have to repopulate, which may lead way to new mutations and new varieties of plants and animals.
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Answer:
h = 67.081 m
Explanation:
Given that,
The time taken by a person to fall down is, t = 2.2 s
The height of the cliff from the ground, h = ?
The distance that the person will fall through the time is given by the formula
S = 1/2 gt² m
Where,
g - acceleration due to gravity
Substituting the values in the above equation
S = 1/2 x 9.8 m/s² x (3.7 s)²
= 67.081 m
Therefore, the height of the cliff from the ground is, h = 67.081 m
Answer:
The height of the image of the candle is 20 cm.
Explanation:
Given that,
Size of the candle, h = 12 cm
Object distance from the candle, u = -6 cm
Focal length of converging lens, f = 15 cm
To find,
The height of the image of the candle.
Solution,
Firstly, we will find the image distance of the candle. Let it is equal to v. Using lens formula to find the image distance.
v is image distance
If h' is the height of the image. Magnification is given by :
So, the height of the image of the candle is 20 cm.
