Why does a CD have a slightly higher interest rate than a typical savings account at a bank?

A CD is a type of deposit account that often pays a higher interest rate than a standard savings account in exchange for restricting access to your funds during the CD term — often between three months and five years. ... You also might have to forfeit a portion of the interest you earned, depending on the bank's policy.

from the figure we get,

the x axis shows   the months and,

the y-axis shows the number of satisfied customer.

each line or each cell in upward direction (y-axis) shows 500.

the appropriate scale for the y - axis is: -

a = 2000 customers

b = 4000 customers

c = 6000 customers

d = 8000 customers

e = 10000 customers

f = 12000 customers

g = 14000 customers