In cocker spaniels, solid coat color is dominant over spotted coat color. If two heterozygous dogs were crossed to each other, what would be the probability of having a first litter of 6 pups, the firstborn with spotted fur, and then among the next 5, 4 with spotted fur and the rest with solid fur; and then a second litter of 7 pups, 1 with spotted fur and the rest with solid fur?

There is no short answer.

Explanation:

Let's say that solid coat is expressed with S and spotted coat color is expressed with s. This means that the two heterozygous cocker spaniels have Ss as their genomes. This results in the probability of 75% solid coat (SS and Ss) and 25% spotted coat (ss) in the offspring.

The probability of the firstborn pup in the first litter having spotted fur would be 25%. The probability of 4 out of the 5 remaining pups having spotted fur is 1/4 x 1/4 x 1/4 x 1/4 which is 1/256.

The probability of the second litter having 1 pup with spotted fur is 25% and the 6 remaining pups with solid fur can be calculated as above by multiplying 3/4 6 times which is 64/4096 or 1.5%.

I hope this answer helps.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.