Here is a question about this article: Transformation, unlike transduction or conjugation, depends on numerous bacterial gene products that specifically interact to perform this complex process, and thus transformation is clearly a bacterial adaptation for DNA transfer. In order for a bacterium to bind, take up and recombine donor DNA into its own chromosome, it must first enter a special physiological state termed competence (see Natural competence). In Bacillus subtilis, about 40 genes are required for the development of competence. The length of DNA transferred during B. subtilis transformation can be between a third of a chromosome up to the whole chromosome. Transformation appears to be common among bacterial species, and thus far at least 60 species are known to have the natural ability to become competent for transformation. The development of competence in nature is usually associated with stressful environmental conditions, and seems to be an adaptation for facilitating repair of DNA damage in recipient cells.
What is the answer to this question: How big can be the transformation level?
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So... between a third of a chromosome up to the whole chromosome


Here is a question about this article: The Śātavāhana Empire was a royal Indian dynasty based from Amaravati in Andhra Pradesh as well as Junnar (Pune) and Prathisthan (Paithan) in Maharashtra. The territory of the empire covered much of India from 230 BCE onward. Sātavāhanas started out as feudatories to the Mauryan dynasty, but declared independence with its decline. They are known for their patronage of Hinduism and Buddhism which resulted in Buddhist monuments from Ellora (a UNESCO World Heritage Site) to Amaravati. The Sātavāhanas were one of the first Indian states to issue coins struck with their rulers embossed. They formed a cultural bridge and played a vital role in trade as well as the transfer of ideas and culture to and from the Indo-Gangetic Plain to the southern tip of India. They had to compete with the Shunga Empire and then the Kanva dynasty of Magadha to establish their rule. Later, they played a crucial role to protect a huge part of India against foreign invaders like the Sakas, Yavanas and Pahlavas. In particular their struggles with the Western Kshatrapas went on for a long time. The notable rulers of the Satavahana Dynasty Gautamiputra Satakarni and Sri Yajna Sātakarni were able to defeat the foreign invaders like the Western Kshatrapas and to stop their expansion. In the 3rd century CE the empire was split into smaller states.
What is the answer to this question: From what did the Satavahana Empire protect much of India?
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So... foreign invaders


Here is a question about this article: A commutated DC motor has a set of rotating windings wound on an armature mounted on a rotating shaft. The shaft also carries the commutator, a long-lasting rotary electrical switch that periodically reverses the flow of current in the rotor windings as the shaft rotates. Thus, every brushed DC motor has AC flowing through its rotating windings. Current flows through one or more pairs of brushes that bear on the commutator; the brushes connect an external source of electric power to the rotating armature.
What is the answer to this question: What does the communicator do?
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So...
reverses the flow of current in the rotor windings