When light travels from a medium with higher refractive index into a medium with lower refractive index, there is a maximum angle (called critical angle) for which all the light is reflected, so there is no refraction.
The value of the critical angle is given by:

when n1 is the refractive index of the first medium, while n2 is the refractive index of the second medium. In our case, n1=1.33 (the water) and n1=1.00 (the air). Putting numbers in, we get
Answer:
54 × 5/18 = 15m/s
Explanation:
to convert km/hr to m/s you multiply by 5/18
Answer:
A Shunt is a passive element, usually resistive, that is used to bypass current around another element, like a meter, that is not able to handle the full current flow. ... A Multiplier is an active element that amplifies a voltage or current to enable a less sensitive device or circuit to make use of it.
Snapping a leaf shut around an insect, I think.