If productCost and productPrice are numeric variables, and productName is a string variable, which of the following
statements are valid assignments? If a statement is not valid, explain why not.

a. productCost = 100
b. productPrice = productCost
c. productPrice = productName
d. productPrice = "24.95"
e. 15.67 = productCost
f. productCost = $1,345.52
g. productCost = productPrice - 10
h. productName = "mouse pad"
i. productCost + 20 = productPrice
j. productName = 3-inch nails
k. productName = 43
l. productName = "44"
m. "99" = productName
n. productName = brush
o. battery = productName
p. productPrice = productPrice
q. productName = productCost

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Apump is used to circulate hot water in a home heating system. water enters the well-insulated pump operating at steady state at a rate of 0.42 gal/min. the inlet pressure and temperature are 14.7 lbf/in.2, and 180°f, respectively; at the exit the pressure is 60 lbf/in.2 the pump requires 1/15 hp of power input. water can be modeled as an incompressible substance with constant density of 60.58 lb/ft3 and constant specific heat of 1 btu/lb or. neglecting kinetic and potential energy effects, determine the temperature change, in °r, as the water flows through the pump.

Which of the following ziegler nichols tuning methods the response of the controller to a step input should exhibit an s-shaped curve? a)-open loop mode b)-closed loop mode c)-both modes (open & closed) d)-none of the modes (open & closed)