Astudent used the distributive property to simplify 9(m - 4). their answer was 9m - 4. which answer choice best describes the student's work? a - the student correctly simplified. the 9 was distributed to the m and now 4 will be subtracted from the product of 9 and m. b - the student made an error. the first factor, 9, was distributed to only one of the terms inside the parentheses. c - the student made an error. 9 should be distributed to the number 4, but not to the variable m. d - the student made an error. 9 should be distributed to the number 4, but not to the variable m. ( ! d: the best answer gets to be and rated! )

linearly: 8560 bacteria

exponentially: approximately 75233 bacteria

step-by-step explanation:

assuming it is not exponential (we would have some really complicated logarithms), let's say it is linear. then, after 5 hours, it increased by 1200 bacteria, so every hour it increases by 240 bacteria. this means that after 19 hours, we get 19 * 240 + 4000 bacteria or 3800 + 760 + 4000 = 7800 + 760 = 8560 bacteria.

because it says round your answer, i will do this exponentially (with a calculator, of course). first, we need to find how much it multiplies by every hour, by taking the 5th root of 52/40 or 13/10. this is approximately 0.167. we still need to add 1 to this, because we are multiplying by that number, not adding that amount of the number. now, we just calculate 4000 * (1.167)^19. use a calculator to get approximately 75232.6, or 75233.