Please help will mark brainliest

What is the common difference in the following arithmetic sequence 7,3,-1,-5

Driving 75 mph, it takes alicia 2 hours to reach the airport to go on a vacation. it then takes her 4 hours to get to her destination with the jet traveling at a speed of 400 mph. how many miles does alicia travel to get to her destination?

Which function is odd check all that apply a. y=sin x b. y=csc x c. y=cot x d. y=sec x