Propón un ejemplo de cada una de las propiedades de la adición de números reales

What is (28 + 7 + 6 + 3) x 1/2 show your work

:24% of students in a class are girls. if there are less than 30 students in this class, how many students are there? how many girls are there?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?