Can someone plzzz help wit this plz

A(t)=728(1+0.04)^t how much money did aditya originally invest

Ben is three times as old as samantha, who is two years older than half of michel's age. if michel is 12. how old is ben?

Someone this asap for a group of students attends a basketball game. * the group buys x hot dogs at the concession stand for $2 each. * the group buys y drinks at the concession stand for $3 each. the group buys 29 items at the concession stand for a total of $70. how many hot dogs did the group buy?