jose，whose mass is 90 KG,has just completed his first bungee

jose，whose mass is 90 KG,has just completed his first bungee jump and is now bauncing up and down at the end of the cord。His osollations have an initial amplitude of 13M and a period of 4.0s。hint：Although not entirely realistic，treat the bungee cord as an ideal spring that can be compressed to a shorter length as well as stretched to a longer length。
a.what is the spring constant of the bungee cord?
b.what is Jose's maximum speed while oscillating
c.Form what height above the lowest point did Jose jump?
d.if the damping constant due to air resistance is 6.0 kg/s,how many oscillations will Jose make before his amplitede ihas decreased to 5.0 处理提问