The work done by the elephant to lift one log is the force multiplied by the height at which the log has been lifted:

And so, the total work done to lift the 7 logs is 7 times the work done to lift each log:
Answer:
T = 60 s
Explanation:
There are 6 poles on the track which are equally spaced
so the angular separation between the poles is given as


so the angular speed of the train is given as


now we have time period of the train given as



Answer:
Acceleration of the car will be 
Explanation:
We have given mass of the ball m = 1600 kg
Force in north direction F= 7560 N
Resistance force which opposes the movement of car 
So net force on the car 
According to second law of motion we know that F=ma
So 

As far as I know acids turn litmus paper red and bases turn it blue. on the pH scale anything under 7 is acid and above is base so I think it is A. I am not totally sure, but that is the best answer I can give you! Good Luck! Hope this helps!!
Answer:
l= 4 mi : width of the park
w= 1 mi : length of the park
Explanation:
Formula to find the area of the rectangle:
A= w*l Formula(1)
Where,
A is the area of the rectangle in mi²
w is the width of the rectangle in mi
l is the width of the rectangle in mi
Known data
A = 4 mi²
l = (w+3)mi Equation (1)
Problem development
We replace the data in the formula (1)
A= w*l
4 = w* (w+3)
4= w²+3w
w²+3w-4= 0
We factor the equation:
We look for two numbers whose sum is 3 and whose multiplication is -4
(w-1)(w+4) = 0 Equation (2)
The values of w for which the equation (2) is zero are:
w = 1 and w = -4
We take the positive value w = 1 because w is a dimension and cannot be negative.
w = 1 mi :width of the park
We replace w = 1 mi in the equation (1) to calculate the length of the park:
l= (w+3) mi
l= ( 1+3) mi
l= 4 mi