Answer:

Explanation:
A body has acceleration when there is a change in the velocity vector, either in magnitude or direction. In this case we only have a change in magnitude. The average acceleration represents the speed variation that takes place in a given time interval.
a)

b)

Answer:
The magnitude of the impulse is 1.33 kg m/s
Explanation:
please look at the solution in the attached Word file
Complete Question:
Which process is not required for an animal to obtain energy from food?
a. Secretion.
b. Digestion.
c. Excretion.
d. Ingestion.
Answer:
c. Excretion.
Explanation:
Excretion is a metabolic process in which living organisms gets their system rid of metabolic waste, water and excess ions. This is usually done with the aid of kidney, skin and lungs in all vertebrates.
Example of excretions are urination, sweating and defecation.
The correct answer is
<span>C) -10.7 m/s
In fact, the first rock is moving upward with velocity +4.5 m/s, while the second rock is moving downward with velocity -6.2 m/s, with respect to a fixed reference frame. In the reference frame of the first rock, instead, the second rock is moving with velocity equal to its velocity in the fixed frame minus the velocity of the reference frame of the first rock:
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