A biologist studies two different invasive species, purple loosestrife and the common reed, at sites in both wetland and coastal habitats. Purple loosestrife is present in 35% of the sites. Common reed is present in 55% of the sites. Both purple loosestrife and common reed are present in 23% of the sites. What percentage of the sites have purple loosestrife or common reed present?

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

Aline passes through 3,7 and 6,9 what equation represents the line

Triangle abc has side lengths: ab = 3.5  cm, bc = 2.4 cm, and ac = 4.2 cmδabc ≅ δhjkwhat is the length of side hj?