Idon't have much time! answer quickly! 2 questions:
1. which system of grouping is in figure 18-2, a or b provides information about the evolution of the three animals
2. according to the cladogram in figure 18-2, what two characteristics do crabs and barnacles share that limpets do not?
you in advance

The correct answer is-

1) Cladogram

2) Molted external skeleton and segmentation.

A cladogram can be described as a diagrammatic representation in a  branching treelike form, which is used to depict phylogenetic relationships among different species.

For every divergence point in a cladogram, the two branching lines show descendance, which indicates divergence of species from a common ancestor. Thus, it is a system of grouping of various organisms.

In the given cladogram, the two characteristics that are shared by crabs and barnacles but not by limpets are Molted external skeleton and segmentation.

ans.

gregor john mendel is known for study of inheritance in pea plants. he used garden pea plant for his study, having alternative traits for various characters. he performed cross-breeding in pea plants to check how characters are transmitted between parents to offspring, such as cross between pure tall and pure dwarf plant. mendel studied the inheritance patterns in pea plants for various generations.

thus, the correct answer includes options and f).

a researcher conducts an experiment on the secretion of a particular hormone in mice. scientists inject mice with a substance that stimulates the production of the hormone. the scientists then test the levels of hormones produced by the mice. the tool used to measure the hormones consistently detects the levels at 10 points lower than the actual hormone levels in the mice. this tool makes measurements, but the measurements aren't .

explanation:

no u