How could the strength of an electromagnet be increased

A. use fewer coils of wire around the nail
B. use more coils of wire around the nail
C. use battery with less voltage
D. use a smaller nail

Classify the descriptions and examples as endocrine or neural control

Ascientist is investigating the effects of salinity on fish development. he places fertilized fish eggs in an aquarium that contains low salinity and observes their development. what factor would improve experimental design the most? place the fish eggs in the open ocean because that is the natural habitat include another aquarium that has normal salinity to compare to the low salinity aquarium include an aquarium that replaces salt with sugar to confirm that the effects are specific to salt grow algae with the fish eggs in order to provide adequate nutrients to the developing embryos

What is genetic variation? -(a) each individual in a population has slightly different genes. -(b) some individuals in a population have more genes than others. -(c) each population of a species has slightly different genes. -(d)some populations of a species have more genes than others.