In Drosophila, the genes for body coloration and eye size are on different chromosomes. Normal-colored bodies are dominant to ebony-colored (very dark) bodies, and normal-sized eyes are dominant to being eyeless. Line A is true breeding for normal body and normal eye, whereas line B is true breeding for ebony bodies and being eyeless. From a dihybrid cross between lines A and B, 400 flies are scored. How many F2 flies are expected to have ebony-colored bodies and normal eyes

Sally and sue were investigating the topic of friction in science. they used a small car and a ramp as seen in the picture to test what they were learning. they knew that they slipped easily on waxed floors but not on carpet, so they decided to change the material on the surface of the ramp to see what happened. they planned to use glass, carpet, aluminum foil, and sandpaper and run the car down the ramp over each surface. what would be the best research question to guide the girls' experiment? a) does the amount of surface area affect the friction on the moving car? b) will the car travel fastest on the glass surface? c) how does the angle of the ramp affect the speed of the car? d)do rougher surfaces tend to create more friction than smooth surfaces?