Answer:
BC and DE
Explanation:
In the given figure, the velocity time graph is shown. We know that the area under v-t curve gives the displacement of the particle.
Area under AB, 
Area under BC, 
Area under CD, 
Area under DE, 
Area under EF, 
So, form above calculations it is clear that, during BC and DE undergo equal displacement. Hence, the correct option is (c) "BC and DE = 4 meters".

Actually Welcome to the Concept of the Projectile Motion.
Since, here given that, vertical velocity= 50m/s
we know that u*sin(theta) = vertical velocity
so the time taken to reach the maximum height or the time of Ascent is equal to
T = Usin(theta) ÷ g, here g = 9.8 m/s^2
so we get as,
T = 50/9.8
T = 5.10 seconds
thus the time taken to reach max height is 5.10 seconds.
Answer:
When broadcasting live on social, keep in mind that the best broadcasts are ones that feel like a conversation between brand and viewer. Unlike other forms of social video, you’ll get more views and engagement if your video
is longer and repeats key points.
Explanation:
When broadcasting live on social media, one should be live for long because in this way one can get more views as audience will increase with time. There should be an interaction with the audience like answering their questions which they write in the comments section. These comments and views will make this video to the top of news feed. Secondly the most important thing is the content of the video. One must focus on the information or knowledge he/she wants to convey and must repeat the key points again and again so that one who has missed the important points will be able catch them later.