manipulated: shape of the container
responding: time it takes to freeze
constants: temperature of water, amount of water, freezing conditions, etc
control group: water freezing in a typical container
2.
manipulated: temperature
responding: the wellness of the battery
constants: type of battery
control group: probably batteries at room temperature or a specific disclosed temperature
3.
constants: the construction of the backpack meaning size, shape, etc. The condition of the cloth
control group: store bough backpack would be good
4.
Type of stain, type of fabric, amount of stain remover, application process of stain remover, amount of time the stain has set
5.
Because you need constants to keep everything else in the experiment the same. Otherwise you don't know what changed your results
Hope that helps
