Answer:
The independent variable is the temperature to which the paint and materials are exposed
The dependent variable is the presence of peeling and cracking of the paint
The constant rates are the paint and material used for each trial
Explanation:
The treatment the to which the paint is subjected = Temperatures from 260 °C to 650 °C
The method of determining the paint quality = By peeling and cracking
The types of paint and materials used = The same paint and material
The independent variable is the variable suspected as the cause of the effect being studied. It is the variable introduced as a treatment
In the question, given that the paint is subjected to different temperatures from between 260°C to 650 °C, the temperature changes introduced is the independent variable
Therefore;
The independent variable = The temperature to which the paint and materials are exposed to
The dependent variable is the effect variable. It is the variable of the property being investigated and it is also the variable that is measured in the investigation
In the question, given that the after heating the paint and material, the scientist check for peeling and cracking, the dependent variable is the occurrence of cracking and peeling at a given temperature
Therefore;
The dependent variable = The presence of peeling and cracking of the paint
The constant rate(s) are variables which are kept constant during the investigation, under the different treatments
The constant rate(s) in the tests are the paint and material, which were kept the same for each trial to reduce the effect of underlying factors that may impact on the result and obscure the relationship between the dependent and independent variables
Therefore;
The constant rate are the paint and material used for each trial
= 
= 9.95 mL
x 100 
x 100 = 0.5 % error