Simplify the expression with the given variable’s ?! 3r-4s, when r= 5 and s= 2/3

Identify the type of observational study described. a statistical analyst obtains data about ankle injuries by examining a hospital's records from the past 3 years. cross-sectional retrospective prospective

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?

Aregular pentagon with a perimeter of 21 inches is dilated by a scale factor of 5/3 to create a new pentagon. what is the perimeter of the new pentagon?