The ball will take 1.15 seconds to hit the floor.
It is given that,
A juggler is performing her act using several balls. The height as a function of time is given by :
[tex]h(t) =-16t^{2} + vt +s[/tex].............(1)
where,
v is the speed of the ball
s is initial height
t is time taken
Putting h(t) = 0 and solving equation (1)
[tex]-16t^{2} + vt +s = 0[/tex]
[tex]-16t^{2} + 15t +4 = 0[/tex]
On solving above equation using graphing calculator and solving for t we get, t = 1.154 second.
Hence, the correct option is (b) " 1.15 seconds ".
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