Which statement about crustaceans is true? *

(A) all have the same number of appendages

(B) all have an internal skeleton

(C) all have an exoskeleton

(D) only some have jointed appendages

C. All have an exoskeleton

Explanation:

Crustaceans is a subphylum

of Arthropoda. The study of crustaceans is knows as carcinology or crustaceology.

They are important sources of food and they consist of crabs, crayfish, prawns etc. They are closely related to insects in terms of morphological(structural) features.

Crustaceans have varying numbers and structure of appendages. However they lack endoskeletons and possess exoskeletons.

the father in the first generation probably had the recessive colorblind trait in his x chromosome. if he and his wife both had the colorblind trait, even if she had 1 recessive and 1 dominant, then that trait would be passed on to their kids.

(since you didn't attach the family tree this is just an assumption)

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !