Covariance measures the linear relationship between two variables. The covariance is similar to the correlation between two variables, however, they differ in the following ways: Correlation coefficients are standardized. Thus, a perfect linear relationship results in a coefficient of 1. The correlation measures both the strength and direction of the linear relationship between two variables.
The Largest True Goldfish Ever Caught. The largest true goldfish on record was measured at 5lbs (2.27 kilograms) and was caught by a 16 year old schoolboy in the UK. This blown-up goldfish was evidently a pet before it ended up into a lake.
Goldfish are actually very complex creatures. Amazingly, they can reach lengths of 12 or more inches and live 10 to 20 years. The oldest goldfish on record was over 40 years! Goldfish are among the hardiest of fish, and can survive through the worst of conditions. They are perfectly adapted to life in a pond, just like their wild carp ancestors.