Okay let me walk you through this, a resistor resists right? its in the name. so you can guess that it would be 4th one down, because if you resist you don't stop, you just slow down. So you should definitely know current is energy, and since electrons is energy you know that current is the second one down. You already have two. Heres a good test taking strategy, the first one says "materials that do conduct electricity just not as well as conductors" so you know that something that conducts electricity well is a conductor, the third one down. now you have 3/5 and you haven't used any real knowledge. So now you are stuck between something that blocks electricity and something that is okay with it. Since you know a conductor does good, wouldnt a semi-conductor be the first one? since it is semi or partially a conductor. Then you are left with insulators to block them out. I hope I left a decent enough explanation. :)
ANSWER

EXPLANATION
First, let us make a sketch of the question:
From the diagram:
=> black line represents North
=> green line represents East
=> blue line represents West
=> red line represents South
From the diagram, we see that at the end of his journey, he returns to his start point.
Since displacement is the measure of the change in the position of an object and the boy's position did not change after the journey, his displacement is:
Answer:
D
Explanation:
A is wrong as otherwise the ocean would be black as light could not pass through it to create images.
B is wrong. This is a weird one as the electromagnetic spectrum attached below shows that radio waves have the least amount of energy vs gamma which has the highest and you can't really compare this to sound waves.
C just straight up false.
D is correct, no way to remember this, just learn it. a couple of facts about transverse waves of google. Electromagnetic waves are a type of transverse waves. These waves do not require a medium to travel. As the name of the waves imply, these waves show electrical and magnetic properties. No any charge occur in the waves. Electromagnetic waves work by the laws of reflection and refraction. They travel as straight lines in a vacuum at a speed of 3 x 10 8 ms -1.
Extra info:
As gamma waves have the highest energy it means that the waves are closer together (the wavelength is smaller) and they create more heat. Also gamma waves go through everything, X-ray only through skin and bounces of dense things like bones, which creates images. These eventually weaken more and more until radio waves do not pass through anything and just bounces around and everywhere which allows you to gain more coverage on a radio then on a cell phone.
Reference point is most often given a value of zero to describe an object's position on a straight line