Answer:
The value is
Explanation:
From the question we are that
The velocity 
The time taken is
The total mass of the train is 
Generally the average power delivered is mathematically represented as
=>
=>
Answer:
Output power of the charger is 9.85 watts.
Explanation:
It is given that,
Output current of the USB charger, I = 1.97 A
The standard USB output voltage, V = 5 V
We need to find the output power of the charger. It can be determined using the following formula as :
P = V × I

P = 9.85 watts
The output power of the charger is 9.85 watts. Hence, this is the required solution.
It is B since they are traveling at the same speed one is positive so the other had to be negative hope this helps;)))))
Consider the upward direction of motion as positive and downward direction of motion as negative.
a = acceleration due to gravity in downward direction = - 9.8 
v₀ = initial velocity of rock in upward direction = ?
v = final velocity of rock at the highest point = 0 
t = time to reach the maximum height = 4.2 sec
Using the kinematics equation
v = v₀ + a t
inserting the values
0 = v₀ + (- 9.8) (4.2)
v₀ = 41.2 