Harnessing tidal power would involve:.a) letting in-flowing and/or out-flowing tide flow through turbines in a dam. b) huge floats mechanically hooked to generators. c) electrodes in the water. d) bioluminescence of marine organisms. e) all of the above

a) letting in-flowing and/or out-flowing tide flow through turbines in a dam.

Explanation:

Tidal power makes use of the energy from the tidal force and wave action in order to generate electricity. it is a predictable source of energy.

Tidal Barrages

The system allows tides to enter, seawater flows via the dam and is trapped into the basin when the tides subside and system’s gates close.

When the tides start to move out, the gates in the dam are opened up this consist of turbines and water begins to flow out, hitting the turbines this eventually turn to produce energy.

Power is produced when the tidal range, which is the difference between low and high tide, has to be more than 5 meters.

d

explanation:

v=uf/(u-f)

= 5.10/(5-10) convex lens has positive focal length

=50/-5

=-10 cm (formed at other side)