PLEASE HELP ASAP I WILL GIVE BRAINLIEST!!

Q1: I'm going to say the fence is a polarizing filter.

Q2: On the second question: (b). BTW, It's not a very well-phrased question (and I'm a particle physicist, so...)

Explanation:

Q1:

So... hard to say for sure the intent here without knowing what you've been learning in class, but a frisbee - being a flat disk - will only go through the fence if it is oriented as shown, much like polarized light will only go through a polarizing filter if the EM waves are polarized in the direction that they will pass through a polarizing filter.

Q2:

It's not a) because ALL waves require a source of energy.  

b) is for sure true and is about energy transfer - mechanical waves need a medium (like water) but EM waves do not. (Early on they thought maybe there was a medium for EM waves... they called it "aether" ... but it was proven via the Michealson-Morley experiment that no the speed of light was an absolute constant - fundamental to special relatively - which meant that light did not travel in any medium!)

(c) - depends on what you mean by "vibration", but yeah... EM waves result in varying electric fields for an observer. However, nothing to do with energy transfer per se (except that those varying fields are what transfer energy to objects that experience them...)

(d) - As above, the speed of light is a constant - cannot change speed ever *in a vacuum*.  However, the speed of light is different in various materials, and can be bent (refracted) or reflected, which means the fields change direction in interacting with matter, although they do not change speed or direction "on their own" (in a vacuum).  Similarly, mechanical waves can change speed or direction when there are changes or discontinuities in the media they travel in.  So, arguably about energy transfer (the direction and speed related to the direction and rate of energy transfer) but not really different between EM and mechanical waves.

Anyway, like I said, it's not a very clear question, so YMMV with my advice here, but (b) is for sure the best single choice.

according to jean piaget, in what stage of cognitive development are children able to understand conservation task?

b. preoperational

just took it