The speed of the wind is changing according to the function V(t)=−t2+30 , where t = time in minutes after 6:00 p. M. And V(t) = wind speed in miles per hour (mph). Which statement best describes the meaning of the equation V(20)−V(10)=−5 ? In a period of 5 minutes, the wind speed increased from 10 mph to 20 mph. The wind speed decreased by 5 mph between 6:10 p. M. And 6:20 p. M. The wind speed increased by 5 mph between 6:10 p. M. And 6:20 p. M. In a period of 5 minutes, the wind speed decreased from 20 mph to 10 mph.

Use addition and subtraction to simplify the following polynomials. a. add polynomials: (3 – 4x + 8x^2) + (–6 + 2x – 5x^2) step 1: rewrite the polynomials without the parentheses. step 2: write the polynomial in descending order and use parentheses around like terms. step 3: add the like terms identified in step 2 to simplify the polynomial. b. subtract polynomials: (3x – 5 – 7x^2) – (–2 + 6x^2 – 5x) step 1: rewrite the polynomials without the parentheses. remember to multiply each term in the second parentheses by –1. show your work. step 2: write the polynomial in descending order and use parentheses around like terms. step 3: add the like terms identified in step 2 to simplify the polynomial.

Plz. yesterday, the snow was 2 feet deep in front of archie’s house. today, the snow depth dropped to 1.6 feet because the day is so warm. what is the percent change in the depth of the snow?

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.