Answer the following question given this paragraph: Consider the ramp in Figure below . It's easier to push the heavy piece of furniture up the ramp to the truck than to lift it straight up off the ground. However, pushing the furniture over the surface of the ramp creates a lot of friction. Some of the force applied to moving the furniture must be used to overcome the friction. It would be more efficient to use a dolly on wheels to roll the furniture up the ramp. That's because rolling friction is much less than sliding friction. As a result, the efficiency of the ramp would be greater with a dolly. Q: What does pushing an object over the surface of a ramp cause? Choices: - Acceleration - vibration - tension - friction A:
friction

Answer the following question given this paragraph: Q: Which carrier molecule becomes less effective at binding oxygen as temperature increases? Choices: - water - helium - hydrogen - hemoglobin A:
hemoglobin

Answer the following question given this paragraph: To begin mitosis, the DNA in the nucleus wraps around proteins to form chromosomes . Each organism has a unique number of chromosomes. In human cells, our DNA is divided up into 23 pairs of chromosomes. Replicated DNA forms a chromosome made from two identical sister chromatids , forming an "X" shaped molecule ( Figure below ). The two chromatids are held together on the chromosome by the centromere . The centromere is also where spindle fiber microtubules attach during mitosis. The spindles separate sister chromatids from each other. Q: What forms when the dna in the nucleus wraps around proteins? Choices: - rna - genes - ribosomes - chromosomes A:
chromosomes