Answer:
D
Step-by-step explanation:
Chemical shift is given as
Frequency/frequency of instrument
Let c = chemical shift
F = frequency
I = frequency of instrument
Chemical shift = frequency/frequency Instrument
1.25ppm = Frequency /400
We cross multiply to find frequency
Frequency = 400 x 1.25
Frequency = 500Hz
Option d is the answer since it is 500hz