Cross the long-finned fish with short-finned fish; if the offspring are all long-finned, the long-finned parent is homozygous.
Imagine that long fins in zebrafish is a dominant trait. A breeder wants to set up a breeding program beginning with homozygous dominant long-finned fish. If she obtains a handful of the rare long-finned fish, how can she tell which if any of these are homozygous for the trait?
True or False

True

Explanation:

In order for the breeder to know if the long fined fish are homozygous. He will have to cross the Long finned with short finned

If the long finned was homozygous, all the F1 will be long finned zebrafish. This is because long fin is dominant over short fin.

However, if the long finned zebrafish were heterozygous. The cross will produce two long finned and two short finned zebra fish.

c. earths continental crust is thicker than its lithosphere.

because, the lithosphere is the outermost layer of the earth/ 100 km thick and is defined by its machanical properties.the lithosphere contains oceanic and continental crust that varies in age and thickness across locations and geologic time. the lithosphere is the coolest layer of the earth in terms of temperature. the term lithosphere should not be confused with the use of "geosphere" which is used to indicate all of earth systems, including the atmosphere, hydrosphere   and biosphere. the surface of the earth can be divided into the continental crust and the oceanic crust.   the continental crust is made mostly of granite while the oceanic crust is made of basalt. the average thickness of the continental crust is 25 miles and the average thickness of the oceanic crust is 5 miles.   three types of rock, igneous, sedimentary, and metamorphic, make up the surface of the earth. that's why 3 option is preferable.