Answer:
page break shows the end of a page.
Answer: Strong 128-bit encryption.
Explanation: An individual character corresponds to 8 bits . So if there are 16 characters then,
16
8=128 bits keys
This makes the 128 bit key encryption the strongest amongst all other options.It is strongest because it is almost impossible to decode the 128-character key by any method e.g.-brute-force method.
Other options are incorrect because the characters given by the other bits are as follows: 
=32 characters
=64 characters
=128 characters
Thus, the strongest character key is of 128 bits. for cipher.
Answer:
Yes, Its a good idea but depends upon type of image. Like adding a logo to all the slides at top left corner is not just good but a must for all as well, when we are preparing official documents. However, other images when decided to be repeated must convey the correct intent in each page. If this is not the case, you need to avoid it. Intent is the most important aspect certainly. For rest see explanation.
Explanation:
Yes, and as mentioned above adding logo and other images meaningfully, and with correct intent is a good idea.
However, images must not be blurred, tiny or stretched. Also proper cropping is a must. The border should be solid as well. And when selecting a lot of images, the images must convey the correct meaning together. Moreover, the aspect ratio after stretching must be same as the original. You can do this in PowerPoint by going to format > crop > fill.
Ensure that watermarks are not revealed. Buy them rather than copy from somewhere for better outcome. And never amputate your readers with a headache creating backgrounds. You will loose readers then. The clip arts must be used in right number, and not a lot of them certainly.
Ensure both text and images are in correct ratios. Avoid using more than 2 images per slide.
Answer:
cyberspace
Explanation:
It is the notional environment in which communication over computer networks occurs.
