Explain why crossing-over is an important source of genetic variation. written response

A60-tooth gear is connected to a 72-tooth gear. if the smaller gear turns 12 times, how many turns does the larger gear make?

This is so important ugh its 25 points

In 2015, about ten percent of total u. s. energy consumption was from renewable energy sources. renewable energy plays an important role in reducing greenhouse gas emissions. when renewable energy sources are used, the demand for fossil fuels is reduced. sanjay and his family want to cut back on their use of non-renewable resources at home. they are thinking of an alternate way to heat their home without adding more greenhouse gases or pollutants to the environment. which renewable resource would not fit into their plan? a) solar power b) burning wood c) constructing a wind turbine eliminate d) generating hydroelectric power