Four scientists collected data on the blood pressure of 30 people.

Which scientist most likely had a problem with experimental design?

Scientist 1
Scientist 2
Scientist 3
Scientist 4

If there was no gravity then their would be no downword force on the football to have it return the the grownd, and if there was no friction (mainly air friction) then there would be no opposing force the stop the ball from moving through the air allowing the ball to travle ∞.

Amplify and switch electrical power and electronic signals

Answer(b) both involve the use of levers;