Answer:
A. The athlete isn’t doing any work because he doesn’t move the weight.
Explanation:
We must remember the definition of work, which says that work is equal to the product of mass by the distance displaced. In this case, the athlete only does work when he lifts the weight from the ground to the point where he holds the weight suspended.
So when he's holding the weight, he doesn't do any work.
Coal and oil.... Fossil fuel is formed from decaying plants/animals who were buried and eventually converted to crude oil, gas by the exposure to heat and the pressure of the earths crust. This takes about 1 million years to happen.
Answer:
Following are the responses to these question:
Explanation:
Since the
is the current of ckt which depend on the reactance which inductor that also enables the ckt and inductor resistance
for capacities
for

When 
then
therefore,
remains at the same so, the maximum current remains the in same ckt.
To solve this problem we will apply the concepts related to the calculation of the speed of sound, the calculation of the Mach number and finally the calculation of the temperature at the front stagnation point. We will calculate the speed in international units as well as the temperature. With these values we will calculate the speed of the sound and the number of Mach. Finally we will calculate the temperature at the front stagnation point.
The altitude is,

And the velocity can be written as,


From the properties of standard atmosphere at altitude z = 20km temperature is



Velocity of sound at this altitude is



Then the Mach number



So front stagnation temperature



Therefore the temperature at its front stagnation point is 689.87K