mohon bantuannya... no 13 beserta caranya...

a. cari k
k = m x w^2
k = 5/1000 (dalam m) x 100 x 100
k = 50

b. Etotal = 1/2 k a^2
1/2 x 50 x 4/100 x 4/100 = 8 x 10^-2 (A)