Find the cardinal number of the set C={x|x∈N,30 where N denotes the set of all natural numbers.

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

1.based of the diagrams what is the the value of x? 2.how would you verify your answer for x

Johnny rode his bike to a friends house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was unable to play. what was his displacement for the total bike ride trip? what could you use as a reference point ? show the steps to solve this problem.