The exact numbers are the ones in a and c.
Work Step by Step
a) 100 is an exact number since a centimeter is defined as precisely 1/100 of a meter b) 1.094 is not an exact number; 1 meter is not exactly 1.094 yards c) The numbers are exact numbers. They can be easily calculated if we know that 0 degrees Celsius equals 32 degrees Fahrenheit and 100 degrees Celsius equals 212 degrees Fahrenheit. d) $\pi$ is a number which has an infinite number of digits. Therefore, it is not exact.