Answer: C. there is more silicon than calcium at the surface of the earth
Explanation:
The answer is a simple radial nervous system.
Echinoderms do not have brains. Around their mouth, they have central rings from which nerves radially run into arms and along the body. Movement is controlled by the branches of those radial nerves.
I would say fossilization
The answer would be letter B.
Solar- technologies convert sunlight into electrical energy either through photovoltaic panels or through mirrors that concentrate solar radiation.
Hydro- a hydraulic turbine converts the energy of flowing water into mechanical energy. A hydroelectric generator converts this mechanical energy into electricity
Tidal- energy is a form of hydropower that works by harnessing the kinetic energy created from the rise and fall of ocean tides and currents, also called tidal flows, and turns into unusable electricity
Wind- turns the propeller like blades of a turbine around a rotor, which spins a generator, which creates electricity
OTEC- plants pump large quantities of deep cold seawater and surface seawater to run a power cycle and produce electricity
Biomass- is burned in a boiler to produce high-pressure steam. This steam flows over a series of turbine blades, causing them to rotate. The rotation of the turbine drives a generator, producing electricity
Geothermal- power plants use steam to produce electricity. The steam comes from reservoirs of hot water found a few miles or more below the earth’s surface. The steam rotates a turbine that activates a generator, which produces electricity
