Answer:b)via radio signals
Explanation: Machine-to-machine technology is the technology that helps in sharing of the real time information of the device that have embedded sensor.They can work without the help of the manual factors.
The data is shared through the help of the radio signals in the devices like turbines vending machines etc for the tracking purpose and managing.
Thus the other options are incorrect because short distance is a disttance, cloud services are for the collection of services and databases contains the data. So, the correct option is option (b).
Answer:

Explanation:
The statements are logically equivalent if they have the same truth tables. So let´s use truth tables in order to determine if they are logically equivalent or not:
The picture that I attached you shows the truth table for each case. As you can see in the highlight columns:

They are logically equivalent because they have exactly the same truth values between each other. Hence, we can conclude that they are logically equivalent.
Implementation hiding i<u>s the encapsulation of method details within a class</u>. Implementation can be interpreted as those specifications which can be altered without altering the correctness of an application. Wrapping data/methods within classes (descriptions of the way all objects of this type will look/act) in combination with implementation hiding is called encapsulation. Information users need to know about behaviors should be available without dependence on implementation specifications.
Answer:
From Networkopoint of view, a node is a redistribution point or communication point or a connection point.
It can also mean devices or data points on a large network Such as laptop, phones, printers, etc
Explanation: