Answer:

Explanation:
Assuming that cars 4 and 5 have same mass so that the momentum
P=mv where m is mass and v is velocity hence
Momentum=0+2mv+3mv=5mv
The final mass is 2m+3m=5m
From aw of conservation of momentum
hence 
Therefore, the speed is 
Ek = 1/2 x m x v ²
1/2 x 620.0 x 9.00 ² = 25,100
Answer:
The correct answer will be-
1. Dependent variable- The growth of plant in the form of height
2. Independent variable- different temperature
3. Constant variable- The amount of water, amount of sunlight, type of soil.
Explanation:
A Scientific experiment must include three types of variables which are: The independent, dependent and the constant variable.
1. Independent variable- The variable which can be modified or changed either on its own or manually. The variable directly influences the variable to be studied. In the given condition, the independent variable is the different temperature provided to the plants.
2. Dependent variable- The variable which is being studied in the experiment and directly influenced by the independent variable is the growth of the plant which is measured in the form of height.
3. Constant variable- The variable which is kept constant throughout the experiment and remains the same which could be the amount of water amount of sunlight and type of soil.