Answer:
Repeated
Explanation:
An experiment must be done multiple times to prove its validity.
hope this helps- Cam ♡
Answer: A. Work is done on the system and heat is transferred from the system for a net decrease in internal energy.
Explanation:
A refrigerator is a device which dispenses heat from the close system to a warmer area or in the surrounding. By dispensing the heat the internal temperature of the refrigerator drops. The system of refrigerator violates the second law of thermodynamics. As it performs the work to cool the region instead of heating the region. The work is done on the system and the internal energy decreases and the heat energy is liberated to the surrounding area. A refrigerator is an open system.
An example of a a predator in the Ethiopian Highlands ecosystem is the
Wolf.The wolf is a carnivore which acts as a predator to other smaller
animals in the ecosystem.
<h3>What is a Prey?</h3>
Preys are mostly smaller animals in which the predators feed on for food.
They are usually herbivores and primary consumers in the ecosystem.
Examples of Preys include:
Read more about Feeding relationship here brainly.com/question/9852437
Answer:
v = 12.86 km/h
v = 3.6 m/s
Explanation:
Given,
The distance, d = 13.5 km
The time, t = 21/20 h
= 1.05 h
The velocity of a body is defined as the distance traveled by the time taken.
v = d / t
= 13.5 km / 1.05 h
= 12.86 km/h
The conversion of km/h to m/s
1 km/h = 0.28 m/s
12.86 km/h = 12.86 x 0.28 m/s
= 3.6 m/s
Hence, the velocity in m/s is, v = 3.6 m/s
