Kruuk et al. (1989) used a stratified sample to estimate the number of otter (Lutra lutra) dens along the 1400-km coastline of Shetland, UK. The coastline was divided into 242 (237 that were not predominantly buildings) 5-km sections, and each section was assigned to the stratum whose terrain type predominated. Sections were then chosen randomly from the sections in each stratum. In each section chosen, investigators counted the total number of dens in a I 10-m-wide strip along the coast. The data are in the file otters. dat. The population sizes for the strata are as follows: a. Estimate the total number of otter dens along the coast in Shetland, along with a standard error for your estimate.
b. Discuss possible sources of bias in this study. Do you think it is possible to avoid all selection and measurement bias?

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.

a triangular prism is a 3 dimensional shape composed of triangles and rectangles. it is made from two triangular bases and three rectangular sides.