A(n) is a sudden, permanent change in a sequence of dna.
allele
chromosome
epigenetic
mutation

According to subpart d, research with children may be eligible for exemption when: the children will be asked to complete a surveythe research involves the use of educational teststhe children will be interviewed by the researcher.the research with children will involve participant observation with researcher interaction.

For 50 pointsfredrika's science teacher asked her to bring in three abiotic items from her backyard ecosystem. which of the following groups of items should she bring? a. a lightning bug, a plug of grass, and a wormb. a smooth rock, some red dirt, and an empty bird's nestc. a ladybug, a spider, and some water from a mud puddled. a caterpillar, a pine cone, and a piece of a robin's egg

Mrs. walter’s husband died in 2016. she has not remarried and has maintained a home for herself and her dependent son, whom she can claim as a dependent. in the summer of 2018, the son was killed in an automobile accident. what is mrs. walter’s filing status for 2018