At midnight, the temperature in a city was 5 degrees Celsius. The temperature was dropping at a steady rate of 2 degrees Celsius per hour.

Write an inequality that represents t, the number of hours past midnight, when the temperature was colder than -4 degrees Celsius. Explain or show your reasoning.
Show all the values of t that make your inequality true on a number line, like the one shown below.
A number line with the numbers negative 4 through 10, in increments of 2, indicated.