Why codon in the sickle cell DNA is altered ?

The energy of blowing wind can be harnessed to create electricity. why is wind considered a renewable energy source? a) wind does not cause destruction of the environment.b) wind turns the blades of a windmill that creates electricity.c) wind provides only a very small amount of electricity to the united states.d) wind comes from atmospheric conditions that are available indefinitely.

Which of the following is a consequence of urban heat islands? increased precipitation downwind of the city? increased precipitation upwind of the city? decreased winds within the city? increased winds within the city?

During which phase does earth see more than half of the moon's surface? 1)first quarter2)third quarter3)waxing gibbous4)waning crescent