Final answer:
The final temperature after a decrease of 1.3 degrees Celsius from -7.3 degrees Celsius is -8.6 degrees Celsius, represented by the equation T = -7.3 - 1.3. The correct option is a.
Step-by-step explanation:
The student's question pertains to calculating the final temperature after a decrease in degrees Celsius. To represent the scenario with equations, we use subtraction for a decrease in temperature.
The correct equation from the options provided is:
a) T = -7.3 - 1.3
Using this equation, we can find the final temperature:
T = -7.3 - 1.3 = -8.6 degrees Celsius
Therefore, the final temperature for that day is -8.6 degrees Celsius. Option b), c), and d) do not correctly represent the decrease in temperature. The correct option is a.