Answer:
a. t=0.5s
b. f=2Hz
c. w =4π
d. k = 78.95 N/m
e. v = 4.39 m/s 
f. Fs=4.835N
Step-by-step explanation:
a. The period of the motion is 
t= 0.5 s
b. Frequency 
f =1 / t
f = 1 / 0.5 = 2 Hz
c. Angular frequency 
w = 2π*f 
w = 2π*2Hz= 4π
d. The spring constant is 
f = 1/2π * √k/m 
k = (2π * f)^2*m =(2π*2Hz)^2 * 0.5 kg
k = 78.95 N/m
e. Maximum speed 
Kinetic energy and spring energy to find the maximum speed 
1/2 *K*x^2=1/2*m*v^2
1/2 * 78.95N/m*(0.35m)^2=1/2*0.5kg*v^2
Solve to v'
v = 4.39 m/s
f. The maximum force on the block from the spring 
Fs= 1/2*K*x^2
Fs=1/2*78.95N/m*(0.35m)^2
Fs=4.835N