please help me solving all the parts of question 10

10. The velocity of a certain particle that moves in a straight line under the v(t)=10ekt , where k is is a positive constant and v(t) in centimeter per second. a) Show that the acceleration of the particle is proportional to a constant. b) What is the initial velocity of the particle? c) At what time is the velocity equal to half the initial velocity? What is the acceleration at this time? [T4,A2,C2]