The question here is how long does it take for a falling
person to reach the 90% of this terminal velocity. The computation is:
The terminal velocity vt fulfills v'=0. Therefore vt=g/c,
and so c=g/vt = 10/(100*1000/3600) = 36,000/100,000... /s. Incorporating the
differential equation shows that the time needed to reach velocity v is
t= ln [g / (g-c*v)] / c.
With v=.9 vt =.9 g/c,
t = ln [10] /c = 6.4 sec.
Add -7y and divide both sides to get one solution (0.20588)
The function would be y = 0.45x, x being the number of seconds, y being the items he can ring up.
For example (this is an example only to show how this equation works), if we were looking at how many items the cashier can ring in 5 seconds, we would make the equation y = 0.45(5), and with multiplication, we can find that they would ring 2.25 items ( y = 2.25 )
If I misunderstood this question or got something wrong, please leave a comment and I can help further.
The answer is 40 is 80% of 50 ☺
The length of JK rounded to the nearest hundredth is 4.72
