If she has a choice and the wiring details are stated on the packaging,
then Janelle should look for lights that are wired in parallel within the
string, and she should avoid lights that are wired in series within the string.
If a single light in a parallel string fails, then only that one goes out.
The rest of the lights in the string continue to shimmer and glimmer.
If a single light in a series string fails, then ALL of the lights in that string
go out, and it's a substantial engineering challenge to determine which light
actually failed.
To solve this problem we will apply the concepts related to energy conservation. Here we will use the conservation between the potential gravitational energy and the kinetic energy to determine the velocity of this escape. The gravitational potential energy can be expressed as,

The kinetic energy can be written as,

Where,
Gravitational Universal Constant
Mass of Earth
Height
Radius of Earth
From the conservation of energy:

Rearranging to find the velocity,
Escape velocity at a certain height from the earth
If the height of the satellite from the earth is h, then the total distance would be the radius of the earth and the eight,


Replacing the values we have that


Therefore the escape velocity is 3.6km/s
F = ma
F = 85×(5-3)÷3
F = 85×(2÷3)
F = 85×0.667
F = 56.67N
The work done on the barbell is -165.62 Nm.
Explanation:
Work done on any object is the measure of force required to move that object from one position to another. So it is determined by the product of force acting on the object with the displacement of the object.
In the present problem, the displacement of the object on acting of force is given as 1.3 m. And the weight of the object which is a barbel is given as 13 kg. As the work is to lift the object from the ground, so the acceleration due to gravity will be acting on the object. In other words, the force applied on the object to lift it should be in opposite direction to the acting of acceleration due to gravity.
Thus, 
Now, the force is -127.4 N and the displacement is 1.3 m.
So, 

So, the work done on the barbell is -165.62 Nm.
Acceleration, in physics, is the rate of change of velocity of an object with respect to time. <span> Anytime an object's velocity is changing, the object is said to be </span><span>accelerating. It can be calculated as follows:
acceleration = 8.2 - 3.5 / 1.5 = 3.1 m/s</span>²
Hope this answers the question.