Please help and show working out thank you

News cameras take an overhead picture of a crowd at an outdoor event journalist then count the total number of people in the picture and use the sample of estimate the total number of people in the crowd this process is an example of

Asequence is defined recursively by the formula  f(n  +  1)  =  f(n)  +  3 . the first term of the sequence is  –4. what is the next term in the sequence? –7–117

Terri makes a quilt using three sizes of fabric squares the side lenght of each fabric square is the square root of the area