How long does it take a car traveling at 45km/h to travel 100 m

What is a neurotransmitter involved in mood reward, addiction, and motor behaviors?

Which one of the following research methods can show cause and effect

In order of decreasing light-transmitting capabilities of materials, which is the correct sequence? a. transparent -> translucent -> opaque b. opaque -> transparent -> translucent c. opaque -> translucent -> transparent d. translucent -> transparent -> opaque