Answer:
Angular acceleration, is 
Explanation:
Given that,
Initial speed of the drill, 
After 4.28 s of constant angular acceleration it turns at a rate of 28940 rev/min, final angular speed, 
We need to find the drill’s angular acceleration. It is given by the rate of change of angular velocity.

So, the drill's angular acceleration is
.
Answer:Broadly speaking, all energy in the universe can be categorized as either potential energy or kinetic energy. Potential energy is the energy associated with position, like a ball held up in the air. When you let go of that ball and let it fall, the potential energy converts into kinetic energy, or the energy associated with motion.
EXAMPLES: There are five types of kinetic energy: radiant, thermal, sound, electrical and mechanical. Let's explore several kinetic energy examples to better illustrate these various forms.
Answer:
The correct statements would be
- Cyanobacteria allowed organisms that rely on oxygen to evolve.
- Cyanobacteria preceded the first photosynthetic organisms.
- Cyanobacteria produced excess oxygen.
Cyanobacteria, also termed as blue-green algae are the prokaryotes which are able to perform photosynthesis.
They were the major contributors of oxygen in the atmosphere and thus helped the organisms that rely on oxygen to evolve.
By the process of endosymbiosis, they lead to the origin of plants. The chloroplasts present in green plants is considered as the cyanobacteria living in the plant cell. It helps in photosynthesis and in return plants cell provides shelter to it.
It is believed that the oxygen released from early cyanobacteria reacted with dissolved iron ions to form iron oxide.
It could cause them to catch animal disease
Explanation:
Xenotransplantation refers to the transplantation of organs or tissues between different species. E.g. Chimpanzee organ (liver) being transplanted into a human body would come under the category of xenotransplantation.
Pigs have come up as prospective organ donors since their organs and tissues are more or less to that of human’s. However, there are issues such as-
- Xenotransplantation of pig’s tissue into a human would allow easier passage for all types of zoonotic viruses.
- Moreover, if transgenic pigs are used instead of natural pigs it can lead to virus mutation as per the human body demands thus leading to increased susceptibility to human infection.
Thus, engrafting of pig’s tissue in the human body poses a significant risk for humans of catching a zoonotic (animal) disease.
Answer:
Transverse wave
Explanation:
The wave is moving forwards from the hand to the point of attachment