Answer:
The focal length of the concave mirror is -15.5 cm
Explanation:
Given that,
Height of the object, h = 20 cm
Radius of curvature of the mirror, R = -31 cm (direction is opposite)
Object distance, u = -94 cm
We need to find the focal length of the mirror. The relation between the focal length and the radius of curvature of the mirror is as follows :
R = 2f
f is the focal length


f = -15.5 cm
So, the focal length of the concave mirror is -15.5 cm. Hence, this is the required solution.
You might want to do a re-erp on this equation
B. How many people were included in the study.
Answer: D (Chloroplasts)
Explanation: The chloroplast goes through a process called photosynthesis. During this process, specialized pigments in the chloroplast absorb sunlight and use this energy to combine carbon dioxide and water to make glucose and oxygen.
The weight of the ball including the air inside is 1.519 N
Explanation:
First of all, we calculate the volume of the ball, which is the volume of a sphere:

where
r = 21.6 cm = 0.216 m is the radius
Substituting,

Now we can calculate the mass of the air inside the ball, knowing that its density is

Its mass is

We also know that the mass of the ball is
m = 0.100 kg
So the total mass is

Finally we can calculate the weight:

where
is the acceleration of gravity. Substituting,

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