The tension in a guitar string is decreased by 36%. Compared to the string oscillating in its 1st harmonic before, the new 1st harmonic wavelength __________, and the 1st harmonic frequency __________.
a. decreases by 20 % , remains the same
b. remains the same, decreases by 20%
c. decreases by 36 % , remains the same
d. decreases by 20 % , decreases by 20%
e. remains the same, remains the same
f. decreases by 36 % , decreases by 20%