When the heated part of the mantle rises through the cooler part, this is an example of

Which would not reduce the amount of green house gasses in the air

When the magnetic domains in a material can be aligned, but eventually drift out of alignment, the material is

Two resistors r1 and r2 may be connected either in series or parallel across an ideal battery with emf ε. we desire the rate of energy dissipation of the parallel combination to be 8.75 times that of the series combination. if r1 = 105 ω, what are the (a) smaller and (b) larger of the two values of r2 that result in that dissipation rate?