7. How many different three-digit identification tags can be made if the first digit must be a 5 and repetitions are not permitted?

List the 10 possible samples (without replacement) of size 3 3 that can be obtained from the population of five officials.

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

The swimming pool is open when the high temperature is higher than 20∘c. lainey tried to swim on monday and thursday (which was 3 days later). the pool was open on monday, but it was closed on thursday. the high temperature was 30∘c on monday, but decreased at a constant rate in the next 3 days. write an inequality to determine the rate of temperature decrease in degrees celsius per day, d, from monday to thursday.