In primary mutant screens, A) mutant flies are identified by morphology and then the mutant genes are isolated and studied. B) mutant flies are created by RNAi using random RNA sequences and then the genes affected identified. C) mutant flies are created by gain-of-function expression of random genes. D) two mutant flies are mated to determine if there is an effect on morphology.

answer; i believe its echoic memory,it is believed to last three to four seconds; good luck

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

hope this