Explanation :
It is given that, the driver accelerates from a stop sign, cruises for 20 s at a constant speed of 60 km/h, and then brakes to come to a stop 40 s after leaving the stop sign.
We know that acceleration is defined as the rate of change of velocity.
Where
dv is the change in velocity, dv = 0 - 60 m/s = -60 m/s
dt is the change in time, dt = 40 s - 30 s = 10 s
So, 
From the graph it is clear that, from 30 s to 40 s the car is decelerating. So, at every second within this time the value of acceleration will be same i.e. 
.
Answer: Contact the National Aeronautics and Space Association
Explanation:
The National Aeronautics and Space Association is an independent organization in US which aims to enable a safe, secure, efficient space journey and launch of new satellites, spacecraft beyond the earth's orbit. It can give better information for the space travel already conducted by the astronauts. Thus will help in writing the report as it is the best place to find the information.
If you are working with electricity most people will measure it in watts.
So, A. watts is your best answer.
Hope I helped! ^w^
C ,A ,B ,D
I think I’m to sure
Answer: When rubbing a balloon with a wool cloth, it puts negative charges on the balloon. Negative charges attract to positive charges. If a balloon is not rubbed with the wool cloth, it has an equal amount of negative to positive charges, so it will attract to a rubbed balloon.
