A car travels at a constant speed of 40 miles per hour down the street for around 0.25 hours. What is its acceleration?

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.

If you divide a speed in miles per minute by 60, you get the same speed expressed in miles

Which of these are physical changes in matter? check all that apply. boiling water a pencil being sharpened exploding dynamite freezing water rotting cheese