What is the percent change if 15 is increased to 21?

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?

Evaluate 8j -k+148j−k+14 when j=0.25j=0.25 and k=1k=1.

With number 11 ( show how you got the answer)