please complete 2,4, and 5 ASAP Thank you

2. [4 points] Give two examples of a constitutive relationship that can be used in a dynamic model. umpedpa vamuermodel disthouted pavameter mogel 3. [2 points] what is the definition of the number of degrees of freedom? Dufl1 Eqivai to the mumber of unknown minus im aedueation 2/2 4. [2 points] Give an example of a parameter that can be used in a dynamic model. 5. [10 points] The flow rate through a valve is originall ( 5L/min. The flow rate was decreased 0,3 ) (L/min) The time constant for the valve is 5S. If the valve bethaves as a first-order process, calculate the time required to reach 85% gf the new steady state