Let s(t)=4t to the thrid power+30t squared+72t be the equation of motion for a particle. Find a function for the velocity.v(t)=  Where does the velocity equal zero? [Hint: factor out the GCF.]t= and t=Find a function for the acceleration of the particle. a(t)=

Find the constant of proportionality. y is directly proportional to x. If x=30, then y=15.

Find the unknown value. 27. y varies jointly with x and the cube root of 2. If when x=2 and z=27,y=12, find y if x=5 and z=8.

When a certain drug is taken orally, the concentration of the drug in the patient's bloodstream After t minutes is given by C(t)=0.06t0.0002t2 where 0t240 and concentration is measured in mg/L .When is the maximum serum concentration reached, and what is that maximum concentration?