Birth to 1 year: 1  In the early months, hold your baby close and read, talk and sing to her. 2  By 3-6 months of age, your baby will start to enjoy looking at mirrors and pictures of faces, shapes, colors.  By 6-12 months of age, your baby will sit in your lap, look at the pictures, touch the book, and put the book in her mouth.
From Wikipedia, the free encyclopedia. Sigma 30mm f/1.4 EX DC HSM mounted on a Canon EOS 40D, hood attached. The Sigma 30mm f/1.4 EX DC HSM is a wide-aperture photographic lens made by the Sigma Corporation, equipped with Hyper Sonic Motor (abbreviated HSM, Sigma's trade name for photo lens focusing technology using ultrasonic motor).
The (Sigma sign) is the 18th letter in the Greek alphabet. Mathematically, Sigma is a summation notation which basically means âsum it upâ. This math symbol was first used by Leonhard Euler, a Swiss mathematician, in representing the addition of a series of mathematical expressions. Golden Ratio Another popular math symbol is the Golden Ratio which is also called the divine proportion or golden section or golden mean.