Which describes the geological time of the first land plants? Mosses appeared after the first flowering plants.
Aquatic Flora appeared many years ago.
The first flowering plants appeared around 240 million years ago.
The first flowering plants were introduced toward the end of the Mesozoic era.

Along wire carrying a 4.2 a current perpendicular to the xy-plane intersects the x-axis at x=−1.7cm. a second, parallel wire carrying a 3.0 a current intersects the x-axis at x=+1.7cm. part a at what point on the x-axis is the magnetic field zero if the two currents are in the same direction? express your answer to two significant figures and include the appropriate units.