Crime-scene work often involves obtaining a DNA sample from a drop of blood to help identify persons who may have been involved. Frequently, the size of the DNA sample is extremely small, too small for easy analysis. Which of the following laboratory procedures could criminologists use to amplify the amount of DNA present? Cloning and gel electrophoresis Cloning and polymerase chain reaction (PCR) DNA splicing and polymerase chain reaction (PCR) Vector amplification and DNA splicing

they have sperm in my gf's mouth

explanation:

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

i believe it's c. the trait for large beaks will be passed on to future generations through natural selection.

since eventually smaller beaks would have to find another source of food or even eventually just die out from the lack of food.