This instrument is called a spring scale.
The simplest way to do this is to set up equivalent fractions, like this-

=

Solve for x by using cross multiplication.
40*2.2= 88
1*x=88
x=88
Therefore, the boy weighs 88lbs.
By definition, acceleration is the change in velocity per change of time. As time passes by, the time increases in value. So, when the acceleration is decreasing while the time is increasing, then that means that the change of velocity is also decreasing with time. So, optimally, the initial velocity and the velocity at any time are very relatively close to each other,
Answer : Total energy dissipated is 10 J
Explanation :
It is given that,
Time. t = 10 s
Resistance of the resistors, R = 4-ohm
Current, I = 0.5 A
Power used is given by :

Where
E is the energy dissipated.
So, E = P t.............(1)
Since, 
So equation (1) becomes :



So, the correct option is (3)
Hence, this is the required solution.
the answer to your question is 15 :)