An experimental group is the group in an experiment that receives the variable being tested. One variable is tested at a time. The experimental group is compared to a control group, which does not receive the test variable. In this way, experimental groups are used to find answers in an experiment.
1 At around 9 months of age, babies begin to pull themselves up to a standing position. 2  By 10 months of age, a baby should be able to grasp objects with thumb and forefinger.
Your baby should be able to follow a moving object with his/her eyes, if it is not moving too fast. Babies are now able to focus and pay attention to the face of a parent or other person near them. Your baby will start reaching for things he/she sees. Four to six months Visual acuity is approximately 20/60. Your baby can now see all colors, although color vision is not as sensitive as an adults. He/she will turn his/her head to look at bright colors and lights. Your baby should recognize objects that he/she has seen and played with before. Babies can now see a three-dimensional view of the world. This allows them to reach and grasp for a finger or rattle, clap hands, or transfer objects from one hand to another. Seven to twelve months Visual acuity is now about 20/30.