PLEASE PLEASE PLEASE HELP ME The Sikhote-Alin Mountains and the Siberian tigers that live on them are separated from other tiger populations. The mountains are a barrier which are an example of a... *
-mass extirpation.
-invasive species.
-mass extinction.
-habitat fragmentation.

Rue or false siblings look simila rbecause they each have some traits of their parents.

Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point

Duchenne muscular dystrophy is a serious condition caused by a recessive allele of a gene on the human x chromosome. the patients have muscles that weaken over time because they have absent or decreased dystrophin, a muscle protein. they rarely live past their twenties. how likely is it for a woman to have this condition? a) women can never have this condition.b) one-fourth of the daughters of an affected man would have this condition.c) one-half of the daughters of an affected father and a carrier mother could have this condition.d) only if a woman is xxx could she have this condition.