Noah is helping to collect the entry fees at his school's sports game. Student entry costs $2.75 each and adult entry costs $5.25 each. At the end of the game, Diego collected $281.25. Select all equations that could represent the relationship between the number of students, s, the number of adults, a, and the dollar amount received at the game.

281.25 − 5.25 a = 2.75 s
a = 53.57 − 2.75 5.25 s
281.25 − 5.25 s = a
281.25 + 2.75 a = s

Malia is observing the velocity of a cyclist at different times. after two hours, the velocity of the cyclist is 15 km/h. after five hours, the velocity of the cyclist is 12 km/h. part a: write an equation in two variables in the standard form that can be used to describe the velocity of the cyclist at different times. show your work and define the variables used. (5 points) part b: how can you graph the equations obtained in part a for the first 12 hours? (5 points) if you can try and make this as little confusing as you can

If x + 10 = 70, what is x? a. 40 b. 50 c. 60 d. 70 e. 80

Need 50 will mark brainliest answer. find the lengths of all the sides and the measures of the angles.