An element has 280 radioactive atoms. It has a half life of 2 years. How long till it reduces to 35 radioactive atoms? Show your working out and units in your answer.

The number of chocolate chips in a bag of chocolate chip cookies is approximately normally distributed with a mean of 12611261 chips and a standard deviation of 118118 chips. (a) determine the 2626th percentile for the number of chocolate chips in a bag. (b) determine the number of chocolate chips in a bag that make up the middle 9696% of bags. (c) what is the interquartile range of the number of chocolate chips in a bag of chocolate chip cookies?

Square a has a side length of (2x-7) and square b has a side length of (-4x+18). how much bigger is the perimeter of square b than square a?and show all work! you so

In which quadrant does the point lie? write the coordinates of the point. a. quadrant ii; (–2, –4) b. quadrant iii; (2, 4) c. quadrant iii; (–2, –4) d. quadrant iv; (–4, –2)