1.1. A biologist is researching a connection between the mass of an animal, M kg, and its expected lifespan, L years.  The biologist suggests that there exists a relationship of the form L=AM^B,  where A and B are constants to be found.

Show that the relationship can be rewritten using logarithms as 

log L =log A +B log M

1.2. Using data from a wide range of animals, when y = log L   is plotted against x = log M on a scatter diagram there seems to be a strong positive correlation.  When the regression line of y on x is calculated, the equation is found to be y = 0.18x + 0.98.

By relating the equation of the regression line to the equation found in (a), or otherwise, find the constants A and B correct to 2 decimal places where appropriate.

1.3. Hence, predict the lifespan of a horse with a mass of 600 kg to the nearest year.

1.4. The biologist concludes the research by suggesting that one way to increase your lifespan is to increase your mass.

Explain, based on these data, why the biologist may be incorrect.