Why isn't nuclear fusion used to generate electrical energy in power plants? a. it requires extremely high temperatures. b. it releases energy per gram than coal does. c. it generates radioactive waste. d. it uses a very rare element.

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.

The density of the block of iron is lees than the density of mercury but the density of the block of iron is greater than the density of water