21+10=31 because you can see that 21 and 10 are in metres while 12 is in seconds so 21+10=31 is the answer.
B force i belive becuase when is done it force
Sry i was knowing the answer i forgot ;(
Wave is a disturbance or energy that propagate through medium from one point to other point
So basically it is a flowing energy that flows into the medium and hence medium particles start oscillating about their mean position to and fro.
This motion of medium particles or this to and fro motion is about their mean position and this will always be cyclic or periodic motion
This means the disturbance or energy continuously flow through the medium such that it will change the position of medium particle and this will be cyclic in order
For an example

so here above equation of wave is a travelling wave in which displacement of medium particle from its mean position is given by "y"
Now we can see that this disturbance depends upon the sine function and it will repeat its same position after every 2 pi time interval as it is cyclic function for this value
Due to this phenomenon of repeatation of its same position we can say that it is disturbance of wave is cyclic.
Answer:
B can take 0.64 sec for the longest nap .
Explanation:
Given that,
Total distance = 350 m
Acceleration of A = 1.6 m/s²
Distance = 30 m
Acceleration of B = 2.0 m/s²
We need to calculate the time for A
Using equation of motion

Put the value in the equation



We need to calculate the time for B
Using equation of motion
Put the value in the equation



We need to calculate the time for longest nap
Using formula for difference of time



Hence, B can take 0.64 sec for the longest nap .