Answer:
Oppositely charged objects attract each other
21. light changes its direction when travelling through a new medium because denser mediums have a higher angle of refraction.
Blood pressure is greater in feet because of gravity
The missing part of the incomplete question is given below:
Which important step of scientific design is Shameka conducting?
repetition
replication
verification of results
using controlled variables
Answer:
Verification of results
Explanation:
The way toward gathering five examples of water from various sources is conveyed to confirm the outcome. By gathering water from five distinct areas of a similar source the analyst can genuinely find out the nature of the water in her region of remain.
On the off chance that after examples are tried it is found the water isn't sound, the outcomes would be acknowledged as it has been appropriately checked and a proper move would be made.
Thus, the correct answer is - verification of results
Answer:
a) 
b) 
c) 
Explanation:
the gravitational potential energy is given by:


The kinetic energy is given by:

the initial kinetic energy is zero because the motion started from rest, so:

applying the conservation of energy theorem:

The work done by the friction force is given by:

the angle of the force is 180 degrees because it's against the movement:
