Using lens equation;
1/o + 1/i = 1/f; where o = Object distance, i = image distance (normally negative), f = focal length (normally negative)
Substituting;
1/o + 1/-30 = 1/-43 => 1/o = -1/43 + 1/30 = 0.01 => o = 1/0.01 = 99.23 cm
Therefore, the object should be place 99.23 cm from the lens.
The correct answer is:
c. convection.
The heating of magma and the continuous cycle of evolution of the magma creating a convection current is the reason for the evolution of Earths tectonic plates.
Explanation:
Tectonic plates are ready to move because the Earth's lithosphere has higher strength than the underlying asthenosphere. Lateral density changes in the mantle appear in convection. Plate movement is believed to be driven by a succession of the motion of the seafloor apart from the extended ridge (due to variations in topography and density of the crust.
Answer:
life in europa is possible due to chemical energy, surface and ocean intracts with one another and give off chemical energy.
Explanation:
the ocean in europa is in contact with the underlying rocky mantle and at high temperatures, its rocks and water interact. oxidization and reduction in which molecules give off and accept electrons occur in it and in deep ocean, when chemically reduction vent fluids interacts with oxygen containing seawater to produce energy that can support micro-organisms and animals.