91Ó°ÊÓ

The given data is

The scatter plot for the given data is

Because the points do not lie on a straight line, the shape is curved.

The pattern in the scatter plot is downwards, hence the direction is negative.

Strength: strong, due to the fact that all points lie within a narrow range of deviations from the basic pattern in the points.

The given data is

From the above scatter plot

Because there is no strong curvature in the scatter plot of position vs log (click-through rate), an exponential model would be acceptable.

The given data is

The logarithm of length is $X$, and the logarithm of heart weight is $Y$.

Find the values from the above table

$$\begin{gathered} a=\frac{∑y·∑x^2-∑x∑xy}{n∑x^2-{\left(∑x\right)}^2} \\ a=1.4674 \end{gathered}$$

$$\begin{gathered} b=\frac{n∑xy-∑x·∑y}{n∑x^2-{\left(∑x\right)}^2} \\ b=-0.1430 \end{gathered}$$

Substitute the values

$y=a+b.x$

$y=1.4674-0.1430x$

The least-square regression equation is

$\ln y=1.4674-0.1430\ln x$.

The given data is

From part (c)

$\ln y=1.4674-0.1430\ln x$

Putting the value of x

$\ln y=1.4674-0.1430\ln \left(11\right)$

$=-0.1056$

Then take the exponential

$$\begin{gathered} y=e^{\log y} \\ y=e^{-0.1056} \\ y=0.784152 \end{gathered}$$

The expected click-through rate is$0.784152\%.$