The figure shows the amount of water in a graduated test-tube. The curved surface shown is called the meniscus. What is the correct reading of the volume of liquid A 7.1 ml
B 7.2 ml
C 6.8 ml
D 6.6 ml

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .