You attend a concert and have a seat that is 70 m away from the stage where the sound is produced. How long does it take for the sound to reach your ears? You take a picture with your phone and send it to your friend who could not come to the concert. She lives in a town 45 miles away. How long does it take until she gets the picture on her phone? Please, include the assumptions that you make.

Given:

distance of observer from the sound source,

distance between the source of image information sender and the receiver,

Assumptions:

speed of sound,

speed of the image information being sent, (we assume it to be nearly the speed of light in vacuum)

Solution:

Time taken by the sound to reach the observer:

Time taken by the image to reach the destination:

i think the answer is b

i guess that visual aids present persuasive examples to what you are presenting, some factors would be theme (does it fit with the color, information, what you are presenting), size (can you see it, is it a big enough span of data/information), and overall look of the visual aid.

hope this : )