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.
Baby Development: 10 to 12 Months. The last development stage in babyâs first year is quite a transition. She isnât an infant anymore, and she might look and act more like a toddler. But sheâs still a baby in many ways. Sheâs learning to: Begin feeding herself.