Expressed in simplified radical form what is the value of √r-√16r when r=2

Look at this pattern ; 1,4,9, number 10000 belongs in this pattern . what’s the place of this number?

Acircus act has 3 times as many elephants as acrobats. jorge noticed that all together there were 56 legs in the circus ring. how many elephants were in the show?

Alistair has 5 half-pounds chocalate bars. it takes 1 1/2 pounds of chocalate,broken into chunks, to make a batch of cookies. how many batches can alistair mke with chocalate he has on his hand?