If the math olympiad club consists of 19 students, how many different teams of 5
students can be formed for competitions?

Determine whether the quadrilateral below is a parallelogram. justify/explain your answer (this means back it up! give specific information that supports your decision. writing just "yes" or "no" will result in no credit.)

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?

What is the value of m in the equation 1/2 m - 3/4n=16 when n=8