Question 1 (Mandatory) (1 point) The height, h, in centimetres, of a piston moving up and down in an engine cylinder can be modelled by the function h(t) = 18 sin(50x/) + 18, where t is the time, in seconds. What is the piston's minimum height? * ( a ) 9 cm Ob) - 18 cm O c ocm O d) 18 cm