Answer:
At 0.713 second the ball will hit the ground
Step-by-step explanation:
The height of an object t seconds after it is thrown from a height of h feet is modeled by the equation:
The ball is thrown from a point 6 feet above ground with an initial velocity, v, of 30 feet per second, equation becomes:
It is required to find the time when the ball hits the ground. At that point, h(t) =0.
So,
Above is a quadratic equation, the value of time is given by :
t = -0.526 s and t = 0.713 seconds
So, at 0.713 second the ball will hit the ground.
The 7 in the hundreds place would represent 700 <span />
160*0.8
The answer is 128
Answer:
Step-by-step explanation:
For this case the solution flows at a rate of 2L/min and leaves at 1L/min. So then we can conclude the volume is given by 
Since the initial volume is 10 L and the volume increase at a rate of 1L/min.
For this case we can define A as the concentration for the salt in the container. And for this case we can set up the following differential equation:
Because at the begin we have a concentration of 8 gr/L and would be decreasing at a rate of 
So then we can reorder the differential equation like this:
We find the solution using the integration factor:
And then the solution would be given by:
And if we simplify this we got:
And after do the integral we got:
And using the initial condition t=0 A= 20 we have this:
So then we have this function for the solution of A:
And now replacinf t= 40 we got:
