Can someone help? 9th grade geometry

55 bridesmaids want to make 325 325 decorations for a wedding. each decoration takes about 212 2 1 2 minutes to make. which response gives the best estimate for the amount of time each bridesmaid will spend making decorations?

Which of the following is correct interpretation of the expression -4+13

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed