The question isn't clear enough, I think it ask us to calculate the linear speed of a point at the edge of the DVD.
Now let's imagine we're a point at the edge of the DVD, we're undergoing a circular motion. Each minute we will complete a circular track 7200 times, now we need to know the distance we travel each turn. The perimeter of the DVD, a circular object is:

Know recall that:

We now need to know how much distance is traveled during a minute or 60 seconds:

Finally we divide this result with t=60 seconds:


Where the distance units were named units as the length unit is not specified in this exercise.<span />
Answer:
1 , 2 and , 4 on usa test prep
Explanation:
Answer:
The power of the distance is -1.
Explanation:
The equation for the electric potential of a point charge is given by 
where V is the electric potential, k is Coulomb's constant (it has a value of
with units
), q is the electric charge of the small charge and r is the distance from the charge.
Now, the power of a number is how many times we multiply that number by itself; we see r appears only once in the equation. So we know the power is 1. But we can see in the equation that k and q are divided by r, which means r is the denominator. This means the power of r is negative (-).
Therefore, the power of r is -1.
temperature rises ? specific heat capacity etc ...
The total resistance of an electric circuit with resistors widener series in the sum of the individual resistances:
Each resistor in a series circuit has a same amount of current flowing through it.
Each resistor in a parallel circuit has the same for voltage of the source applied to it.
When was this is are connected in parallel, the supply current is equal to the sum of the current through each resistor. In other words the currents in the branches of a parallel circuit add up to the supply current. When resistors are connected in parallel they have the same potential differences across them.