Hi please help me calculate this and explain step by step how to calcualte standard deviation and correlation, coefficient.

2.5 Standard Deviation and Correlation Between 1999 and 2002, the shares of SKF and Volvo had the following return per year: 1999 2000 2001 2002 SKF -12 % -5% 23% 2% Volvo -15 % 11% 34% .6 % Use this information to estimate a) The standard deviation of the SKF share b) The correlation coefficient between the SKF and Volvo shares