Answer:

Explanation:
Close to Earth's surface, the force of gravity that pulls an object towards the ground is
(2)
where
m is the mass of the object
g is the acceleration due to gravity, which is
close to Earth's surface
This is an approximation of the general formula of gravity valid only close to Earth's surface. The more general formula is
(1)
where
G is the gravitational constant
M is the Earth's mass
m is the object's mass
r is the distance of the object from Earth's center
At the Earth's surface,
r = R (Earth's radius), and by calling the following factor

we see that eq.(1) becomes eq.(2).
Answer:
B) Angular velocity
Explanation:
The equivalent of Newton's second law for the rotational motions can be written as:

where
is the net torque applied to the object
I is the moment of inertia
is the angular acceleration
From the formula we see that when a constant net torque
is applied, then the object also has a constant angular acceleration,
.
But we also know that

where
is the angular velocity: so, a constant angular acceleration means that the angular velocity of the object is changing, so the correct answer is
B) Angular velocity
(moment of inertia and center of gravity do not change since they only depend on the mass and the geometry/shape of the object, which do not change)
Density depends on mass and volume so option D is correct answer. Hope this helps!
Answer:
A lot of the earth oxygen comes from the ocean around 50%-80%
Explanation:
Answer:
<em>a) 3.6 ft</em>
<em>b) 12.4 ft</em>
Explanation:
Distance between mirrors = 6.2 ft
difference from from the mirror you face = 1.8 ft
a) you stand 1.8 ft in front of the mirror you face.
According to plane mirror rules, the image formed is the same distance inside the mirror surface as the distance of the object (you) from the mirror surface. From this,
your distance from your first "front" image = 1.8 ft + 1.8 ft = <em>3.6 ft</em>
b) The mirror behind you is 6.2 - 1.8 = 4.4 ft behind you.
the back mirror will be reflected 3.6 + 4.4 = 8 ft into the front mirror,
the first image of your back will be 4.4 ft into the back mirror,
therefore your distance from your first "back" image = 8 + 4.4 = <em>12.4 ft</em>