Answer:
One when it enters the glass slab from air and second time when it enters the air through glass slab. When light rays travelling through air enters glass slab, they get refracted and bend towards the normal. Now the direction of refracted ray changes again when it comes out of the glass slab into air.
1.5 m/s is the velocity.
9.3 m is the length of aisle, over which Distance will be covered.
Time is demanded in which the child will move the cart over the aisle with 1.5 m/s.
v=S/t
and,
t=S/v
Put values,
t=9.3/1.5=6.2 s
Complete Question
The speed of a transverse wave on a string of length L and mass m under T is given by the formula

If the maximum tension in the simulation is 10.0 N, what is the linear mass density (m/L) of the string
Answer:

Explanation:
From the question we are told that
Speed of a transverse wave given by

Maximum Tension is 
Generally making
subject from the equation mathematically we have




Therefore the Linear mass in terms of Velocity is given by

I would have to say Texas because, obviously, its on the coast, and because I know for a fact Oklahoma is VERY prone to Tornadoes and I also know Dallas (and surrounding areas) has a few tornadoes a year:)
I hope I helped:)
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