Two cars approaching each other, The first car is a police car that moves at 72 km/h while the second car moves at 90 km/h, The police car started its siren with a frequency of 650 Hz. If the speed of the sound is 350 m/s, then what is the frequency of the sound heard by the driver of the second car from the police car?

The roller coaster from problem #1 then tops a second hill at 15.0 m/s, how high is the second hill? 91.5 m 79.2 m 80.0 m 68.5 m

In positive numbers less than 1, the zeros between the decimal point and a non-zero number are blank significant

This is important. 1. which of the following is an si base unit for measuring length? (2 points) inch gram meter mole 2. which of the following units for distance is an si unit? (2 points) centimeter foot inch yard 3. which of the following tools should a scientist use to measure an object in meters? (2 points) electronic balance pan balance tape measure thermometer