Answer:
D. The rate of change must be 20 pounds per minute.
Step-by-step explanation:
At time 0, the amount of sand is 200 lb. Time zero is when it starts, so it is also called the initial time. The initial value is 200 lb, so choices A and B are wrong.
Now look at the difference from time 0 minutes to time 1 minute. The amount of sand went from 200 lb to 220 lb. The amount of sand placed in 1 minute is 20 lb, so the rate of change is 20 lb per minute. That makes choice C wrong and choice D correct.
Answer: D. The rate of change must be 20 pounds per minute.
2 tons = 4000 pounds and so 1/4 ton = 500 pounds, so the answer is 4500 pounds
4, 8, 12, 16 because they are all multiples of 4 and 2
Answer:
7.2
Step-by-step explanation:
1. Natalie needed 40 minutes to get to school. In hours 40 minutes is 40/60= 2/3 hour (because there are 60 minutes in an hour). so her speed is 14.4/(2/3)= 14.4*3/2= 21.6 mph.
2. Britany needed 40+20= 60 min. 60 min= 1 hour. so she needed 1 hour her speed is 14,4/1= 14.4mph
3. The difference 21.6-14.4=7.2 is the answer .
