In the cassette shown in Figure 1a, two different lox sites are used. What sequences in the lox sites must he different to prevent the two sites from recombining with each other? (d) When two or more different GIT variants are expressed in a neuron, the final color is a blend that reflects the amount of each GFP present. In mice with three cassettes, one GFP variant is expressed from each cassette (assuming that the lox sites preclude recombination between. Ten different colors are possible. Describe the combinations leading to the different colors.