You will have to use this formula:

Final Velocity (V) = 4m/s
Initial Velocity (Vo) = 8m/s
Acceleration (a) = ? m/s^2
Time (t) = 2 secs
Then:
-> 4 = 8 + a x 2
-> 4 - 8 = 2a
-> -4 = 2a
-> a = -4/2
-> a = -2 m/s^2
Ps: It's value is negative because the she was in retrograde motion.
Answer: Her acceleration is -2 m/s^2.
Answer: the speed at which it falls toward the Earth.
Explanation:
A bullet travelling across Earth's surface with some horizontal velocity is classical example of projectile motion.
Projectile motion is an idealization of the motion under the action of gravity neglecting the influence of the air (no drag force nor friction).
This kind of motion is the result of two independent motions: vertical motion and horizontal motion.
The observed net velocity is the vectorial sum of the vertical and horizontal velocities.
The horizontal velocity is constant, since there is not any force acting in the horizontal axis. Thi is, the object, following the first Law of Newton (inertia law) tends to continue in uniform rectilinear movement (with zero acceleration).
The vertical velocity, this is the velocity at which the bullet falls toward the Earth, is influenced (accelerated) by the action of the gravity of the Earth. So, the vertical velocity is accelerated by the pull of the Earth.
Vertical and horizontal velocities are independent of each other, which means that the speed or the magnitude of the horizontal velocity does not affect the speed at which an object (the bullet) falls toward the Earth.
Answer:
The battery supply the greatest current with the 20-W bulb
Explanation:
The electrical power at a certain time by a two-terminal device is the product of the potential difference between the terminals and the current intensity that passes through the device. For this reason the power is proportional to the current and voltage. Mathematically can be written as:

Let:

The voltage remains constant for every case so:

Then:

Analyzing the equations it makes sense that the battery supplies the highest current with the 20 W bulb, because the power only depends on the voltage and the current, if the voltage remains constant, the only reason for the power to increase is due to current.
Complete Question:
Suppose that an asteroid traveling straight toward the center of the earth were to collide with our planet at the equator and bury itself just below the surface. What would have to be the mass of this asteroid, in terms of the earth’s mass M, for the day to become 25.0% longer than it presently is as a result of the collision? Assume that the asteroid is very small compared to the earth and that the earth is uniform throughout.
Answer:
m = 0.001 M
For the whole process check the following page: https://www.slader.com/discussion/question/suppose-that-an-asteroid-traveling-straight-toward-the-center-of-the-earth-were-to-collide-with-our/
Answer:
Momentum of 2nd ball is

direction is given as

Explanation:
As we know that there is no external force on the system of balls so momentum before and after collision will be conserved
So we have

now after collision momentum of two balls is must be same as initial
so we have


so we have


for other component we have


Momentum of 2nd ball is given as


direction is given as


